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Trident Renewal

Volume 591: debated on Tuesday 20 January 2015

I beg to move,

That this House believes that Trident should not be renewed.

It is a pleasure to move the motion, which stands in my name and those of my right hon. and hon. Friends in the Scottish National party, Plaid Cymru—the party of Wales—and the Green party. I am also pleased that the motion is supported by other Members, such as the hon. Member for Islington North (Jeremy Corbyn), who has a long-standing, principled position on this issue.

I thank, in advance, the Secretary of State for Defence for replying to this SNP-Plaid Cymru debate and the Under-Secretary of State for Defence, the hon. Member for Ludlow (Mr Dunne), who has responsibility for defence equipment, support and technology, for closing the debate, and the shadow Secretary of State for his participation on behalf of the official Opposition.

Today’s debate is the first opportunity to debate Trident replacement since the publication of the Government’s 2014 update to Parliament on Trident, published on 18 December. That document confirmed that a further £261 million had been reprofiled to be spent on the project ahead of the maingate stage, when MPs will decide whether to authorise construction of new submarines, thereby confirming that Trident is not subject to the Government’s austerity agenda. The document also confirms that the maingate decision will be reached in early 2016. MPs re-standing for election in 2015 and candidates for all parties can expect to be asked by electors how they would vote on Trident.

This debate also offers the first opportunity for the Government and Members to report back from the international conference on the humanitarian consequences of nuclear weapons, held in December in Vienna, and comes ahead of a demonstration on scrapping Trident taking place this Saturday in London, organised by the Campaign for Nuclear Disarmament. The event starts outside the Ministry of Defence on Horse Guards avenue, just off Whitehall, at noon, and I encourage as many people as possible who want Trident scrapped to attend.

I also put on the record the sincere appreciation of myself, my colleagues and others in the House to Kate Hudson of CND UK, John Ainslie of CND Scotland and Ben Folley, who supports parliamentary CND, as well as all colleagues in other disarmament and non-proliferation organisations.

The hon. Gentleman is being fulsome in his praise for CND. Does he think that that organisation was right during the cold war to dismiss the Soviet threat?

I do not think anybody should dismiss threats at any time, but the question is whether one believes that the threat of catastrophic nuclear annihilation worked. I happen to believe that nuclear deterrents have not worked, and there are plenty of examples of conflicts that were not avoided—

Forgive me, but I want to make some progress. The right hon. Gentleman will have an opportunity to make a speech later, and I look forward to hearing it.

The time has come to put down a marker about scrapping Trident and not replacing these weapons of mass destruction. At present, a UK Trident submarine remains on patrol at all times, and each submarine carries an estimated eight missiles, each of which can carry up to five warheads. In total, that makes 40 warheads, each with an explosive power of up to 100 kilotons of conventional high explosive—eight times the power of the atomic bomb dropped on Hiroshima in 1945, killing an estimated 240,000 people from blast and radiation.

The hon. Gentleman and I have agreed on a number of foreign policy and defence issues, but can he not see that recent events, even on NATO’s border, again remind us of the importance of retaining the ultimate insurance policy in order to help keep Britain and its allies safe?

The difficulty with that position, of course, is that, were it true, it would mean that Germany, Italy and Spain were not safe and required nuclear weapons. In fact, it is the same argument made by the North Korean regime, which believes it needs nuclear weapons to protect itself. It is a dangerous argument to pursue.

I have yet to hear a supporter of Trident convincingly explain in what circumstances they would be prepared to justify the killing of hundreds of thousands of innocent men, women and children and the causing of massive environmental damage to the world for generations to come. Those are the consequences of using nuclear weapons, and surely if one has them, one has to be prepared to use them. I have yet to hear anybody give an example of circumstances where they would be prepared to kill millions of people.

Will the hon. Gentleman explain in what circumstances he would be in favour of using nuclear weapons?

Will the hon. Gentleman explain the logic of his party’s position? It thinks that nuclear weapons are an abomination, but wants an independent Scotland to remain part of NATO, which is an explicitly nuclear alliance founded on the concept of overall nuclear protection.

The hon. Gentleman overlooks the fact that the position of the SNP on NATO is exactly the same as that taken by the Governments of Denmark and Norway—countries that have provided the most recent NATO Secretaries-General. Those countries do not want to possess or host nuclear weapons, which is exactly the SNP’s position, but that has not precluded their participation in NATO. Perhaps having countries take that position might offer the opportunity to change the global approach to nuclear weapons currently pursued by NATO and nuclear-hosting states.

On the basis of the hon. Gentleman’s long-standing and principled support for nuclear weapons, I would be pleased to take an intervention.

In return, I acknowledge the seriousness of the hon. Gentleman’s point about not finding anybody prepared to kill millions of people, but the logical conclusion of that standpoint is that we remain pacifists —[Interruption.] Let me explain. It would mean we could never declare war on any country, whatever the circumstances, because when we do, millions of people inevitably die. The question is, therefore: how do we prevent war? We do it by showing someone that they cannot attack us with these weapons without suffering similar retaliation.

I like the hon. Gentleman a great deal, but I note that even he, one of the leading supporters of nuclear weapons, could not give an example of circumstances where he would be prepared to see the killing of hundreds of millions of people.

The case is stronger than ever for embracing the non-replacement of Trident, which would offer serious strategic and economic benefits, as outlined in the June 2013 report “The Real Alternative”, including,

“improved national security—through budgetary flexibility in the Ministry of Defence and a more effective response to emerging security challenges in the 21st century”


“improved global security—through a strengthening of the non-proliferation regime, deterring of nuclear proliferation and de-escalation of international tensions”.

Does the hon. Gentleman agree that opposition to Trident is not limited to CND or parties such as ours, but includes many in the military? The former British armed forces head described nuclear weapons as “completely useless” and “virtually irrelevant”.

The hon. Lady makes a good point. We are hearing ever more—and respected—people from within the defence community understanding the consequences of the replacement of Trident and the displacement effect that would have on conventional defence within the MOD budget.

I will come to that last issue shortly, but first I want to return to the advantages outlined in the 2013 report “The Real Alternative”, including

“vast economic savings—of more than £100 billion over the lifetime of a successor nuclear weapons system, releasing resources for effective security spending, as well as a range of public spending priorities”

as well as our

“adherence to legal obligations including responsibilities as a signatory to the nuclear Non-Proliferation Treaty (NPT)”,

and—think about this—the

“moral and diplomatic leadership in global multilateral disarmament initiatives such as a global nuclear abolition treaty and the UN’s proposed Weapons of Mass Destruction Free Zone in the Middle East”.

All this would be possible if the UK Government were prepared to embrace a new approach to weapons of mass destruction.

What evidence is there that if we got rid of our nuclear weapons, anybody else would get rid of theirs? Would the French give up their nuclear weapons? Would the Russians?

If common sense were to prevail, it would have a positive impact on other countries. In the first instance, we have to be responsible for the decisions we make in this country, but I remember that when President Nelson Mandela announced he was changing the South African Government’s position on nuclear weapons, he was lauded for it by Members on both sides of the House. I think the UK would be lauded for making a similar decision.

I am going to make some progress now. I have given way generously to Members on both sides of the House.

The benefits that I have outlined from the 2013 report could inform the strategic defence and security review that will follow the general election if we were to recast the UK’s approach to nuclear weapons. The reasons for doing so should be obvious to all; they were written about this week in an article, which I would commend to Members, by Paul Mason of “Channel 4 News”. He wrote:

“Russia, jihadis or cyberwarfare—which is the most urgent of the new threats we face? The forthcoming strategic review will force the British military establishment to ask difficult questions. It must separate real threats from imagined ones.

It is in this context that Britain’s hapless defence establishment has to carry out yet another strategic defence and security review. The last one, in 2010, was a valiant effort to impose philosophical coherence on policies, commitments and projects that had become self-perpetuating, strategically meaningless and financially unsustainable. It did not succeed.

In 2010, the essential problem boiled down to two things: maintaining (and modernising) Britain's capacity to do expeditionary warfare, as in the Falklands, Iraq and Afghanistan; and boosting the strategic end of the armed forces—Trident and the Royal Navy—so that we could still claim to be a world power.”

It is worth reflecting on what Paul Mason wrote because of the squeeze to UK conventional defence capabilities in recent years. We have seen significant cuts to personnel, basing, capabilities and, frankly and sadly, too often a substandard approach to the safety of our service personnel.

Members are well aware of the recent difficulties the MOD is in, in terms of cutting regular troop numbers and filling the gaps with reserves. Bases have been closed, including the end of flying operations from two out of three air bases in Scotland. Crucial capability gaps have been exposed, including the absence of a single maritime patrol aircraft since the scrapping of the entire Nimrod fleet. I observe that the Irish Air Corps has more maritime patrol aircraft than the UK at present. In recent weeks in my constituency, one has been able to regularly see maritime patrol aircraft from other countries operating from RAF Lossiemouth, helping to fill a capability that the UK currently has no concrete plans to fill.

Similar shortcomings have been exposed with other capabilities needed to deal with

“violations of national airspace, emergency scrambles, narrowly avoided midair collisions, close encounters at sea, simulated attack runs and other dangerous actions”.

As has been officially confirmed, the Royal Navy has on a number of occasions “gapped” the provision of fleet ready escort vessels; that is, there was no availability of the appropriate vessel to patrol and screen in UK waters.

My constituents have on a number of occasions been able to see the Admiral Kuznetsov, the largest vessel in the Russian northern fleet, and it has been widely reported about the MOD initially depending on reports from Scottish fishing boats before Royal Navy vessels interdicted the visiting vessels from Russia after being dispatched from the south coast of England.

In recent years we have also had to go through a variety of issues where service personnel equipment malfunctioned or was not up to the appropriate safety standard. Most recently, and tragically, this was exposed after the death of three of my constituents aboard two RAF Tornados that collided above the Moray firth. The Tornado fleet still does not have collision avoidance systems fully installed, decades after they were recommended, and there are no concrete plans or timetables for that potentially life-saving equipment for Typhoons or F35 jets. The MOD has the wrong priorities, investing billions in nuclear weapons that it can never use but not properly managing the conventional armed forces which are so necessary.

The national security strategy noted in 2010 that, in a period of changing security threats, it would be sensible to consider how ending the Trident replacement programme would release resources that could be spent on more effective security measures. What commitment will the Secretary of State give to the national security strategy informing the strategic defence and security review on the issue of nuclear weapons? In 2010, the NSS downgraded the threat of a nuclear weapon conflict without the SDSR downgrading the role of nuclear weapons in our military capability. That mistake should not be repeated in 2015.

The Defence Committee, in its report “Deterrence in the Twenty-First Century”, argued that at some point in the future the core role of nuclear weapons could be achieved by the deployment of advanced conventional weapons. The NSS and SDSR 2015 should model and scenario-plan such situations, and allow MPs to assess the findings, before we commit further billions to the construction of Trident replacement. Ahead of a final decision on the construction of Trident replacement submarines at the 2016 maingate, the role of SDSR 2015 should be to deliver the most open consultation and debate on the role of UK nuclear weapons and whether we should maintain them at all.

Does the Secretary of State recognise that with the national security strategy placing international terrorism, cybercrime and major accidents and natural hazards such as coastal flooding at the top tier of threats to the UK, recent experience suggests that these areas need greater resources, rather than the false priorities of the nuclear deterrent?

On the cost of Trident replacement, we know from studies, including “In the Firing Line”—an investigation into the hidden costs of replacing Trident—that the costs are astronomic and approach £100 billion. It is not just the costs of development and construction. It is also about the in-service running costs over decades. It is worth noting that despite the fact that Parliament has not given maingate approval for Trident replacement, the MOD has already spent between £2 billion and £3 billion on what are called long-lead items.

Most recently, news emerged about the purchase of the “common missile compartment” that is being built in the US at a cost of approximately £37 million. The spec of the common missile compartment has 12 launch tubes and runs contrary to claims by the MOD in the 2010 SDSR that it will

“reduce the number of operational launch tubes on the submarines from 12 to eight”.

Also the UK’s disarmament ambassador, John Duncan, told the UN that the plan was to

“configure the next generation of submarines accordingly with only eight operational missile”


The Royal United Services Institute has estimated that the construction cost of Trident replacement will consume 35% of the procurement budget by the early 2020s. The Minister should be concerned that the cost overruns we have seen with other MOD major projects, such as the Astute submarines, Queen Elizabeth aircraft carriers and A400M refuelling aircraft, will be replicated with Trident replacement and will further impact on resources for other equipment and capabilities.

Has the Secretary of State read the recent media reports that the replacement of Britain’s nuclear deterrent means that his Department will be forced to make more significant cuts to troop numbers unless the next Government agree to keep real-terms increases to the defence budget—something that is not being offered to other Departments?

The hon. Gentleman is making a strong case. Has he made any estimate of the savings that might be made if the House were to vote for the motion and the Government decided to follow that as a policy, bearing in mind that the Government might still wish to proceed with submarine capability?

As I have outlined, there are a number of reports that the through-life costs are nearly £100 billion. There is an issue as to how much one is spending year on year on the existing Trident fleet and then the construction costs, which will peak, I think, between 2019 and 2030.

The former Armed Forces Minister is, I think, concurring with that. It is billions and billions of pounds every year that could be saved and reprioritised. Given all the debates that we are currently having on austerity, the growth of food banks and many other issues—no doubt there are great supporters of the MOD who would wish to see increased spending within the MOD—there are alternatives. A significant amount of money could be saved were one to vote for the motion or if we were to ensure that, at the general election, as many Members as possible are returned to this place who share the views of those of us who wish to see Trident scrapped.

The hon. Gentleman has been very generous with his time. Has he calculated the cost to UK manufacturing of not going ahead with the submarine successor programme at this late stage?

Occasionally I hear from Members who have a constituency interest, and I understand that they want to stand up for firms in their constituency. What I would say to them—I represent a constituency with a very significant defence footprint—is that there are alternatives to spending £100 billion on Trident, and it cannot be beyond the wit or imagination of the Government to look at alternatives for those people with amazing engineering and design skills. They do not need to produce nuclear weapons to have successful careers or, indeed, for their companies to be successful.

I congratulate the hon. Gentleman on his choice of Opposition day motion. He will be aware that the west of Scotland is very dependent on defence jobs. Does he agree that both the Scottish Government and the Westminster Government should be investing heavily in defence diversification, because that is essential if we are going to put our communities in a position where they are not reliant on one particular weapons system?

Indeed. The hon. Lady makes a very strong point, and I am pleased that there are Members in other parties who are clearly supporting the direction of the motion before us. Of course, it is not beyond the wit of Government or companies in the defence sector to concentrate their efforts on the conventional areas of defence rather than on nuclear submarines which have to be one of the most expensive ways of creating and maintaining jobs.

May I take my hon. Friend back to the question of costs and try to put some numbers on this? Is it not the case that according to the last comprehensive assessment, the cost was something in the order of 9% of the MOD budget, around £2.9 billion a year, moving to around £4 billion throughout the 2020s? Does that not give a clear indication of the scale—the quantum—of the money we are wasting on these systems?

My hon. Friend makes a good point and it is what I was trying to outline in response to the interventions from those on the Liberal Democrat Benches. This is about many billions of pounds about which we have a choice: do we want to invest in something we can never use, or do we spend the money in an entirely more beneficial way for society as a whole?

Does the Secretary of State recognise the assessment that during the next decade more than £40 billion is due to be spent on submarines—among them, Trident’s replacement submarines—and that this figure is more than is due to be spent on new land equipment and air equipment combined? Does he agree that the waste of £4 billion with the scrapping of the Nimrod patrol aircraft is now being replicated with the expenditure of £4 billion on the Trident replacement submarine programme ahead of the maingate decision?

The scrapping of Nimrod has limited Vanguard’s operational effectiveness and must mean that the scrapping of Trident is now more certain. What cost has been incurred by the MOD in requesting the deployment of maritime patrol aircraft by allied forces since October 2010, now that Vanguard operates without the support of Nimrod? On how many occasions has the MOD requested deployment of MPA by allied forces since October 2010, now that Vanguard operates without the support of Nimrod?

The issue of Trident replacement comes at a time when the humanitarian consequences of nuclear weapons are being taken seriously by the international community. In December the overwhelming majority of countries attended the international conference on the subject hosted by the Austrian Government. After the US Government confirmed their attendance, the UK relented on its intended boycott and attended in an official capacity, which I welcome. A number of Members of the House, including me, attended the conference, which had a huge impact, forcing attendees to confront the calamity of what would actually happen should there be a planned or unintended nuclear explosion. The UK and other countries need to give a commitment that they will take this issue seriously.

Does the Secretary of State agree with the International Committee of the Red Cross’s findings that global cooling as a result of nuclear conflict could cut food production for many years and put 1 billion people at risk of starvation worldwide? Is this stark warning not further evidence that we must act on disarmament and scrap Trident? Does he not agree that publishing a UK assessment of the global atmospheric consequences of nuclear war would be a positive contribution to the international discussion on the humanitarian consequences of nuclear weapons? Will the Government ensure that the issues raised at the Vienna conference are discussed at the meeting of the P5 nuclear weapons states in February?

While on the international issues relating to Trident, may I say to the Secretary of State that it is high time the Government stated their support for a new legal instrument prohibiting nuclear weapons that would complement our disarmament commitment under article 6 of the non-proliferation treaty? It is time that the Government recognised that the success of past international bans on weapons of mass destruction such as landmines, cluster munitions and chemical and biological weapons must be applied to nuclear weapons. Does the Secretary of State recognise, as those on the Opposition Benches do, the success of past international bans on weapons of mass destruction such as landmines, cluster munitions and chemical and biological weapons, and that this principle must be extended to nuclear weapons?

Before concluding, may I seek clarification relating to the Trident maingate decision that will follow if this vote is unsuccessful today? Will the maingate decision for Trident replacement be published as a report and discussed as a stand-alone issue, separately from the strategic defence and security review? Will the Secretary of State and the shadow Secretary of State both commit to a binding vote of the House at the maingate decision point for Trident replacement?

In conclusion, today’s debate and vote are an important opportunity to show that there is opposition to Trident renewal at Westminster. May I thank all the constituents who have lobbied all of us in past days, sending e-mails and messaging us via Twitter, encouraging us to vote for the motion?

Opposition to Trident is of course particularly strong in Scotland. It is opposed by our faith communities, including the Church of Scotland, the Roman Catholic Church, the Episcopal Church and many others among our faith communities. It is also opposed by the Scottish Trades Union Congress and the Scottish voluntary sector. Opinion opposing Trident is covered fully in today’s The National newspaper, which splashes on a new opinion poll that shows that, of those with an opinion, 60% of respondents in Scotland do not want Trident. Today, sadly, I fear that the Labour party will not represent the majority of its own supporters: in that poll it is clear that a significant majority of Labour voters agree with the SNP in not wanting Trident in Scotland. In the forthcoming general election, we have a huge opportunity to underline our opposition to Trident by electing MPs who have a policy opposed to Trident—in Scotland, that is the SNP; in Wales, it is Plaid Cymru; and in England, it is the Green party. With polls showing that we may very well hold the balance of power after the next general election, we will do everything we can to ensure that Trident replacement does not go ahead.

Today’s debate is about the primary responsibility of any Government: the security of our nation, our freedoms and our way of life. It is not about short-term politics. Whatever the current threats to this country, we cannot gamble with tomorrow’s security. That is why this Government, and all previous Governments for the last six decades, have retained an operationally independent nuclear deterrent, and today this Government are committed to maintaining that credible, continuous and effective minimum nuclear deterrent based on Trident and operating in a continuously at-sea posture for as long as we need it.

We also committed in the 2010 strategic defence and security review to renew our deterrent by proceeding with the programme that Parliament approved in March 2007 by a majority of 409 to 161 to build a fleet of new ballistic missile submarines. For 45 years, Britain has kept a ballistic missile submarine at sea, providing the ultimate guarantee of security against nuclear attack or nuclear blackmail 24 hours a day, 365 days a year. In December I saw that deterrent for myself at Faslane, and let me pay tribute to the crews of Vanguard, Vengeance, Victorious and Vigilant, their families and all those whose support has been essential to Operation Relentless, our continuous at-sea deterrent patrols. It is Faslane that is truly Britain’s peace camp. Whether we like it or not, there remain approximately 17,000 nuclear weapons globally. We cannot uninvent those weapons.

Does my right hon. Friend recall that during the Scottish referendum a number of people said that somehow, because there was a base in Scotland, the rest of England was getting away without having bases related to our nuclear deterrent? It is worth reminding people that from my bedroom window I can see the towers of Aldermaston, Greenham common and the royal ordnance factory at Burghfield. The defence footprint relating to the support of our nuclear deterrent is as important throughout the United Kingdom as it is in Scotland.

My hon. Friend is absolutely right. From Aldermaston and Burghfield to Barrow and Scotland, the United Kingdom together has an interest in the nuclear industry.

Does my right hon. Friend also recognise that Devonport plays a significant part in this matter, because it has the licence for the refitting and refuelling of our nuclear submarines?

I certainly recognise the importance of Devonport and all our naval bases in sustaining our naval operations, including the submarine fleet.

In the context of 17,000 nuclear weapons globally, we cannot gamble with our country’s national security. We have to plan for a major direct nuclear threat to this country, or to our NATO allies, that might emerge over the 50 years during which the next generation of submarines will be in service. We already know that there are substantial nuclear arsenals and that the number of nuclear states has increased. Russia is modernising its nuclear forces, actively commissioning a new Dolgoruky class of eight SSBN vessels, preparing to deploy a variety of land-based ICBM classes, and planning to reintroduce rail-based intercontinental missiles. North Korea has carried out three nuclear tests, threatened a fourth, and carried out ballistic missile tests in defiance of the international community. Iran’s nuclear programme remains a real concern: we see a worrying lack of progress from Iran with the international agency on the military dimensions of its nuclear programme.

The Secretary of State is right to discuss some of the new, emerging external threats, but the major external threat faced by this country is from IS—from jihadists. Would they not be encouraged if we threatened them with nuclear weapons?

There are of course current threats to this country from ISIL and the jihadists, as, indeed, there are from Russia’s behaviour over the past year or so, but we must also plan for future threats to this country, including nuclear threats. Some may well argue, like the hon. Gentleman, that in the face of terrorism and the other immediate threats that we have seen over the past year, a nuclear deterrent is somehow less relevant. That is an argument, but we have never suggested that those other threats should or can be countered by the nuclear deterrent. We are clear that the nuclear deterrent is the only assured way to deter nuclear threats.

Others have suggested that we should move away from continuous patrols and have a part-time deterrent, as if our enemies did not work the full week, but there is simply no alternative to a continuous at-sea deterrent that can provide the same level of protection and the ability to deter an aggressor. We know that because successive Governments have looked at the different options for delivering a deterrent capability. Most recently, the Trident alternatives review in 2013 demonstrated that no alternative system is as capable or cost-effective as a Trident-based deterrent. It also found:

“None of these alternative systems and postures offers the same degree of resilience as the current posture of Continuous at Sea Deterrence, nor could they guarantee a prompt response in all circumstances.”

All the previous studies have also shown that four submarines are required to maintain the continuous posture.

I wanted to intervene earlier, at the end of my right hon. Friend’s arguments about the nature of the gamble that one would be taking with the future security of the United Kingdom by not having a nuclear weapons system. Is not the rather difficult truth that we are making a series of risk assessments and gambles about what we spend on defence and the particular type of defence we buy? While it is funded from the defence budget, Trident comes at the expense of a larger Army, Navy and Air Force, so it is all part of a wider risk assessment, not, as the Secretary of State has suggested, an absolute. If there was no money left for anything except Trident, is that really the decision that we would take?

My hon. Friend is of course right to say that we must assess future risks and the capabilities that we will have to deal with them. All I can say to him is that every successive Government who have looked at the future threat have, in the end, decided to continue to renew our continuous at-sea deterrent. In a world that is becoming more dangerous, there are no alternatives that offer the level of protection and security that this country needs.

Let me be clear, particularly to the Scottish National party, about what we are planning to replace and when. Subject to a maingate decision in 2016, we are planning to replace the current Vanguard submarines—not the Trident missile or the warheads. We are planning to replace the submarines in the late 2020s, by which time our Vanguard submarines will be 35 years old.

The Secretary of State has spoken about the need to take defence and security seriously and the necessity of nuclear weapons to achieving that. Is he saying that nations that do not have nuclear weapons are not taking their defence and security seriously?

No, I am not. I am saying that countries such as ours that have nuclear weapons cannot simply uninvent them; a responsibility comes with those nuclear weapons, and I will come on to explain how we should discharge it.

Let me be clear about the decision that we are going to take in 2016. With the approval of Parliament, the previous Government began the design phase of that decision. In May 2011, we announced the assessment phase, and since then we have reported progress to Parliament annually—most recently, as the hon. Member for Moray (Angus Robertson) pointed out, just before Christmas. We are now more than halfway through that five-year, £3.3 billion assessment phase, the main purpose of which is to refine the design and mature the costs ahead of the maingate decision. After all, this is the largest British submarine project in a generation and one of the most complex ever undertaken by British industry. Of that £3.3 billion of assessment costs, I can confirm that so far we have invested around £1.2 billion as part of the assessment phase. The Under-Secretary of State for Defence, my hon. Friend the Member for Ludlow (Mr Dunne), will be giving further details of those costs when he winds up the debate.

I want to be clear with the House: no submarines are being built before the maingate decision in 2016. However, as with any major programme of this complexity, it is essential and more cost-effective to order now certain items that would delay the programme if we were to wait until the maingate decision. Such items include propulsion components, generators, main engines, condensers and electrical distribution components.

I am grateful to the Secretary of State for giving way so generously. Given how much work has been done on this matter in the Ministry of Defence—he is well supported by a large team of civil servants—will he confirm at the Dispatch Box today the total cost of Trident replacement, including its through-life costs? Is it approaching £100 billion or not?

I do not recognise the £100 billion figure, and it is not possible to answer that question until the maingate decision is made which will be put before this House next year.

Let me turn directly to the issue that the hon. Member for Moray quite rightly and fairly put to me—the issue of affordability.

If we are going to talk about through-life costs, is it not important to point out that the amortised costs of our nuclear deterrent will be only some 6% of the overall defence budget or 0.3% of gross domestic product? The idea that cancellation of this programme will pay for all the goodies outlined by the Scottish National party—one presumes that the SNP will want to carry on building different types of submarine at the these yards in any case—is just moonshine.

My hon. Friend who, having served as shadow Defence Secretary, knows a great deal about this issue, is absolutely right. These are replacement submarines that are going to last us until 2060, so it is very important to look at the cost of the project over the next 45 years.

I want to make some progress. Given the £38 billion hole in the defence budget that we inherited from the shower opposite, this Government have scrutinised the procurement programme to ensure value for money. We have identified savings and we will continue to submit the programme to rigorous scrutiny. Let me assure the House that no part of that programme will be exempt. As I have just said to my hon. Friend the Member for Harwich and North Essex (Mr Jenkin), we are talking about maintaining a capability in service until 2060—for the next 45 years.

We told the House in the 2011 parliamentary report that the cost of the four submarines was estimated to be around £25 billion at out-turn prices. Those costs, of course, will be spread over 25 years. Indeed, if the costs were spread evenly, it would represent an annual insurance premium of around 0.13% of total Government spending. Let me put it another way. Crossrail is costing us around £14.8 billion. Replacing four 16,000-tonne submarines will cost around £25 billion; Crossrail 2 will cost around £27 billion. I hope that provides some context.

Let me now turn to the position of the various parties. The SNP has set out very clearly its opposition to the renewal of Trident. I believe and suggest to the House that that is a highly irresponsible position. It would sacrifice the security of the United Kingdom on the wrong-headed notion that opposes nuclear in all its forms and on the basis of cost savings that would be minuscule compared with the impact on our national security and the damage to our economy, to jobs and to the submarine building industry.

HM Naval Base Clyde is, by the way, the largest single employment site in Scotland, and it is set to increase to 8,200 jobs by 2020 when all of the Royal Navy’s submarines will be based at Faslane. It is the SNP that would put all those jobs at risk. Indeed, the SNP spokesman, the hon. Member for Moray, who has regularly raised the issue of maritime patrol aircraft and foreign submarines, does not seem to see anything odd about wanting the capability to spot other countries’ submarines without making the case for retaining our deterrent in the first place. It is pretty hard to deter our enemies when we do not have the means to do so.

We should also note the nonsense of somehow promising a nuclear-free Scotland. In 2013, the percentage of electricity generated in Scotland from nuclear power increased to nearly 35%—nearly double that of England. Indeed, an independent Scotland would rank seventh in the nuclear league table of EU member states. I do not think, of course, that we should expect consistency from an SNP that wants to dispense with nuclear weapons, but wants also, as the hon. Member for Barrow and Furness (John Woodcock) pointed out, to join NATO—a nuclear alliance. Indeed, according to the document of November 2013, “Scotland’s Future”, the SNP would allow nuclear-armed vessels to use Scottish ports. Perhaps the hon. Member for Moray could explain some of those inconsistencies.

The Secretary of State was unable to tell us earlier what the through-life costs of Trident replacement would be, so let me ask him a second question: when are the UK armed forces going to have a maritime patrol aircraft in service? When will that be?

On his first question—I notice that the hon. Gentleman has not addressed any of the inconsistencies I pointed out—I have already made it clear that we cannot be final about the full-length costs of the renewal until we come to take that maingate decision next year. That will be explained to Parliament. So far as maritime patrol aircraft are concerned, we inherited a situation in which some 21 Nimrod aircraft were supposed to be available by 2003, yet when we came to office seven years later, none was available. As part of the painful decisions we had to take to regularise the defence budget and sort out the £38 billion black hole, it was necessary to cancel a programme that had not in any case delivered. The hon. Gentleman asked me when we were going to examine this matter again, and the answer is very clear: we will, of course, look at that particular capability, along with other capabilities, as part of the strategic defence review, which will be initiated immediately after the general election.

On the issue of security, I have been arguing for some two or three years that Iran had no intention of giving up its ability to make weapons-grade fissionable material and that it is intent on building a nuclear weapon, which is the only reason why it is pursuing its particular plan. Does my right hon. Friend recognise that that is now the case, and that Iran simply wanted to ease the sanctions for a short time? Should we not now be really frightened of that threat from the middle east?

Indeed, we should certainly be concerned about the lack of progress in the talks that have been dragging on for months now, and we should be particularly concerned about the military dimension to Iran’s nuclear programme.

Let me deal now with the position of the official Opposition. On 14 November, the shadow Defence Secretary and the shadow Foreign Secretary wrote to the Prime Minister declaring that Britain should maintain

“a minimum credible independent, nuclear deterrent, delivered through a Continuous At-Sea Deterrent”.

However, on 5 January this year, the Leader of the Opposition told Andrew Marr that

“we have got to have the least-cost deterrent that we can have, and that’s my philosophy.”

How, then, can we explain this apparent shift away from the continuous at-sea deterrent? Perhaps it has something to do with the comments of the leader of the SNP who, in talking about coalition, said that Labour would

“have to think again about putting a new generation of Trident nuclear weapons on the River Clyde.”

The public and those whose jobs depend on this programme have a right to know whether the Labour party would be prepared to trade our security if that were the price of power, and I offer the hon. Member for Gedling (Vernon Coaker) the opportunity to make that clear.

I think that the Defence Secretary used wise words when, at the beginning of his speech, he said that we should not use this issue to play short-term politics. Let me gently warn him. We—he and I, and his party and mine—have worked constructively on this issue during difficult times in recent years. I hope that when the shadow Defence Secretary speaks, the right hon. Gentleman will take it from him—if he will not take it from me—that we remain absolutely committed to the statement that he read out. We remain absolutely committed to an independent minimum credible strategic deterrent delivered by means of the submarine programme that we started in government and will finish. A least-cost deterrent is, to our mind, exactly the same as a minimum deterrent. If the Defence Secretary wants to spend more than least costs, he should say so now.

What I am seeking, and what I have still not heard, is a recommitment to a continuous at-sea deterrent, but those words seem to have slipped out of Labour’s position. I hope that, when we hear from the hon. Member for Gedling—

The Defence Secretary read out our policy, and my hon. Friend the Member for Barrow and Furness (John Woodcock) reiterated it. Our policy is quite clear: we want a minimum independent credible deterrent based on continuous at-sea deterrence, and of course we want to provide it in the most cost-effective way possible. Indeed, when he reads Hansard tomorrow, the Defence Secretary will find that that is exactly what he said a few moments ago.

I think that the House will be grateful to the hon. Gentleman for clarifying that he is still committed to a continuous at-sea deterrent. I hope that he will send a copy of those words to the Leader of the Opposition, so that there can no longer be any lingering doubt in Scotland about whether or not this is a continuous at-sea deterrent.

The right hon. Gentleman is putting up a sterling smokescreen for the Government’s position, as many of his Back-Bench colleagues know. He talks of coalitions. He is not getting on with this because he is in an unholy coalition with the Liberal Democrats, who are preventing him from taking action. He is making a good show of it, but, as he says that he is being clear, let him now be clear to the House.

The right hon. Gentleman anticipates me, because I now want to turn—indeed, I think we all now want to turn—to the position of the Liberal Democrats. On the one hand, the Liberal Democrats have said that they want to spend billions to

“replace some of the submarines”,

and to make our deterrent part time. They have also committed themselves—at their most recent conference—to allowing our submarines to go to sea with unarmed missiles. Those would be pointless patrols, and that is a pointless nuclear deterrent policy. There are no Liberal Democrats in the Ministry of Defence, and the fact that they have adopted such a reckless and, frankly, dangerous approach explains why.

This country faces the threat of nuclear blackmail from rogue states. It is therefore contemptible for the Scottish nationalists or the Liberal Democrats to suggest that they might use the ultimate guarantor of our freedom and independence as some kind of bargaining chip in some grubby coalition deal. To put it more simply, it is only the Conservative party that will not gamble with the security of the British people.

While the Secretary of State is dealing with the Liberal Democrats—only two of whom I see in the Chamber today—will he confirm that a policy of sending unarmed submarines to sea and waiting for a crisis to arise, then sending them back to port to be rearmed while the enemy stands idly by, is actually more dangerous than a policy of keeping them in port all along? Will he also confirm that there will never again be a deal between the Conservatives and the Liberal Democrats to delay the maingate decision, as there was in 2010? That is something with which he had nothing to do, but which should never have been allowed to happen.

Let me assure my hon. Friend, in response to his first point, that we are not planning to make future deals of any kind with the Liberal Democrats. On the contrary, we hope to be returned in May with an absolute majority that will restore defence policy to the hands of a Conservative Government. As for my hon. Friend’s first point, he is entirely right to draw attention to the absurdity of an unarmed submarine, perhaps several hundred miles from its base, asking our enemies to hold off for a time while it returns to be kitted out with missiles before heading off on patrol again. That is an absurd policy, and we rather look forward to hearing the Liberal Democrat spokesman trying to justify it.

Will the Secretary of State return to the point that was raised by the hon. Member for Na h-Eileanan an Iar (Mr MacNeil), and pursue the logic of his argument? If the Secretary of State believes that nuclear weapons are so essential to our security, will he tell us whether he agrees that it is legitimate and logical for every country in the world to seek to apply them? Yes or no?

I do not think that that logic follows at all, but I am about to turn to the issue of disarmament—which has been quite fairly raised—and our obligations under the non-proliferation treaty.

Let me be clear: we hope never to use nuclear weapons, but to go on delivering a deterrent effect. However, we also share the vision of a world that is without nuclear weapons, achieved through multilateral disarmament. Retaining a nuclear deterrent and seeking to create the conditions for a world free of nuclear weapons are not mutually exclusive options. Indeed, I am happy to announce that the Government have now met their 2010 strategic defence review commitment to reduce the number of deployed warheads on each submarine from 48 to 40, and that the total number of operationally available warheads has therefore been reduced to 120. Unfortunately, those reductions have not encouraged other states seeking a nuclear weapons capability to forgo their attempts; nor have they encouraged some other states that already possess nuclear weapons to follow our example. It is our conclusion that it would be rash further to disarm unilaterally while the capability to threaten us remains.

We ascribe the utmost importance to avoiding any use of nuclear weapons, to preventing the spread of nuclear weapons and nuclear weapon technology, and to keeping nuclear weapons safe and secure. We are working hard to ensure that the forthcoming review conference on the nuclear non-proliferation treaty—which is the cornerstone of global efforts to prevent the spread of those weapons—is successful, and next month we will host a conference in London for the five nuclear non-proliferation treaty states.

As I have said from the outset, the first duty of any Government is to ensure the security of the nation, its people and our vital interests. Defending the nation has always been challenging, and never more so than in a nuclear age. It was complex in the first nuclear age of cold war certainties, and it has become even more complex in this second nuclear age, when the problems of proliferation have become sharper and the emergence of new nuclear states has become a reality. We are now in an age of uncertainty and confrontation. History teaches us that the defence of this country means being ready for the unexpected, and that means a full-time nuclear deterrent—not one that clocks off for weeks or months at a time, or one that patrols pointlessly. The need for the nuclear deterrent is no less now than it has ever been, and I urge my right hon. and hon. Friends to vote against the motion.

May I apologise at the outset, Madam Deputy Speaker, for the fact that I have a long-standing constituency engagement and I will not be here for the wind-ups? However, I am confident that both Front Benchers will say only good things about me.

There is a well-known saying in the peace movement that a unilateralist is a multilateralist who means it, and I am one of those. Whatever I have to say today about nuclear weapons goes for all nuclear weapons, and when the British Government, of whatever persuasion, say they want to rid the world of nuclear weapons and when they signed the non-proliferation treaty committing themselves to do just that, I also expect that they mean it. As one of only nine nuclear-armed states, the UK cannot escape its duty to progress disarmament talks. So why would we seek to upgrade Trident for another 50 years without exploring what might be done to bring forward multilateral nuclear disarmament? Why do we not ask ourselves whether spending up to £100 billion on weapons of mass destruction is actually the best way to defend the people of this country, when we cannot raise millions out of poverty or fund our precious national health service? Why do we not ask? It is because too many politicians in this country—we just heard such a speech—remain locked in cold war thinking when much of the world has moved on.

The right hon. Lady says that most of the world has moved on. Has she had any intimation from President Putin that the Russians have any intention of engaging in discussions with her about nuclear disarmament? Has she heard from the North Koreans that they intend to abandon their nuclear capability? How does she respond to my right hon. Friend the Secretary of State’s comment that we have reduced our capability and it has made not one jot of difference to those other nations with nuclear weapons?

The hon. Gentleman is citing countries that are of course the minority—the nuclear-armed states. They all have the same attitude as him: they all have cold war thinking. Many of them have reduced their nuclear arsenals, but they remain more dangerous today.

I will try to deal with this in the same theoretical terms as the right hon. Lady is trying to do. If her argument is that we have moved on from the cold war—it must be noted that at the height of the cold war she, as the head of CND, wanted us unilaterally to disarm—the point is that there can be no guarantee that we will not move back into a cold war or face some other threat. We cannot know what threats will arise over the next 30 to 50 years, which is why we need an array of deterrent weapons.

The hon. Gentleman says we cannot know what will happen in the future, but we have a pretty good idea. The threats that were part of the cold war scenario are very different from those we face today.

The right hon. Lady is making an important speech about the way we think about these issues. Does she agree that the threats emerging in the world at a geopolitical level relate to terrorism? Does she agree that a nuclear bomb is no use at all against terrorists?

I agree with the hon. Lady, but, interestingly, the Government do not, and I will address that point, too.

So what do the true believers say Trident renewal is for? Three threat scenarios are usually advanced: the re-emergence of a major nuclear threat, which is code for Russia; new states acquiring nuclear capability, which is code for Iran; and state-sponsored nuclear terrorism. Russia is behaving badly, it is modernising its nuclear arsenals and it is threatening Ukraine, but why would Russia specifically target Britain for a nuclear attack? We have to ask the same question of Iran, surrounded as it is by nuclear-armed Pakistan on one side and nuclear-armed Israel on the other: what would be the motivation for an attack on the UK? Is it not clear that, however unpalatable, painstaking diplomatic negotiation with this regime aimed at preventing its acquisition of nuclear weapons is more likely to succeed than military threats?

On the Ukraine example, the nuclear deterrent is going to ensure, as it has done for many years, that any war—God forbid we have one—is conventional, not nuclear. Ukraine could turn nasty, as Mr Gorbachev was warning only the other day, so we need the ultimate deterrent to fight a war—if we ever need to—at a conventional level, not a nuclear one.

All the hon. Gentleman is advocating, of course, is conventional war, which can kill hundreds of thousands of people, as we see in Iraq. He is not making an argument. We need to look at where the real threats are and where real security lies. I will argue that real security lies in nuclear disarmament.

It is on the third scenario, state-sponsored nuclear terrorism, where nuclear deterrence is least credible. The UK has promised—this is official policy—a proportionate response to a state that sponsored a nuclear attack, and a mechanism is in place to trace the perpetrators. The nuclear material will be sent to the Atomic Weapons Establishment at Aldermaston for analysis before a retaliatory attack is ordered. Can anyone imagine what might happen in those hours or days when analysis was under way? When that is concluded, would the Secretary of State, in the cold light of day, give the order to fire even a single Trident missile? Of course, if he did so, he would immediately be charged with a crime against humanity, but he does not even have that power. He conveniently forgets, as he did throughout his speech today, that Trident is not independent and is assigned to NATO; it is the United States that would call the shots. So why is it, when 47 out of 50 sovereign European states feel more secure without nuclear weapons than with them, that this country remains so blinkered?

Does my right hon. Friend also recognise that those other members of NATO are part of the nuclear umbrella of NATO and agree to NATO nuclear policy?

My hon. Friend needs to go back and look at his geography. There are not 47 sovereign states in Europe which belong to NATO—

The NATO ones do, but if my hon. Friend listened, he would know that I referred to 47 sovereign states, and they are not all members of NATO by any means.

My right hon. Friend is making an excellent speech. Does she appreciate that almost all my constituents and millions of Labour supporters up and down the country cannot understand why, when we are seeing massive cuts in our public sector and welfare state, we are going to spend upwards of £20 billion on a weapons system that will not make us safe and is not genuinely independent?

The right hon. Lady mentioned that 47 Governments of the 50 in Europe do not have nuclear weapons. On the UK Government’s logic, their description of countries not taking their defence and security “seriously” would apply to those countries. Does she think that is an appalling position for the UK Government to hold about our allies and friends in Europe?

The hon. Gentleman makes a good point. Nuclear weapons have no utility. They cannot be used to advance any cause or secure any territory without the most devastating effects. The true believers present them as benign, silently gliding under the oceans or quietly snoozing in bunkers doing no harm, but it is not so. Some 18 months ago, a book called “Command and Control” was published detailing more than 1,000 nuclear accidents in the United States. Its author, Eric Schlosser, spent six years researching and submitting freedom of information requests. The results are terrifying and would be unbelievable if they had not come directly from official military sources. Historic accidents range from the proverbial spanner being dropped, causing a fuel leak, leading to a missile explosion, and a warhead being blown off, to a nut being left off a bomber, resulting in the engine catching fire and the fire only failing to reach the bomb bay due to the prevailing wind. Today, there is far more dependence on computer technology than on the mechanical, but there is no consolation in that. In 2008, an engineer went to a Minuteman silo, realised that there had been a fire and that the fire alarm had failed. Luckily, the fire burned itself out before it got to the missile. In 2010 at the same base, online contact was lost for an hour with 50 Minuteman missiles—a computer chip had come loose, but it could have been a cyber-attack.

Even more terrifying is the true story of Stanislav Petrov, now portrayed in a film called “The Man Who Saved The World.” Petrov was a colonel in charge of a Soviet nuclear early warning centre when an alarm went off signifying that five American nuclear missiles were heading towards the USSR. Petrov took it on himself to refuse to follow protocol and did not send the signal for a retaliatory strike. He believed that the alarm had to be a malfunction, and he was right, but just suppose somebody else had been on duty. Had a nuclear exchange occurred at that time, we know that the world’s eco-system would have been destroyed. Today we are told that nuclear arsenals are smaller, which is true, and that the world is a safer place, which is not true.

In 2007-08, several groups of scientists published new and peer-reviewed research on the effects of a regional exchange of nuclear weapons, such as might occur between India and Pakistan. The firepower used for modelling purposes was 50 Hiroshima-sized bombs on each side, which represents just 0.03% of the explosive power of the current global arsenal.

We have known since 1945 of the immediate effects of nuclear weapons—blast, firestorms and radioactivity that would kill millions, but only those who are near the targets. This is what the scientists say of the indirect effects: about five megatons of black smoke would be produced and, as the smoke lifts into the stratosphere, it would be transported around the world. The climatic effects of this high layer of smoke would be unprecedented, plunging the planet into temperatures colder than the little ice age that began in the 17th century. Worldwide agriculture would be severely affected. A larger nuclear exchange, including that involving UK weapons, would result in a true nuclear winter, making agriculture impossible. Both scenarios show climate effects lasting more than a decade and up to 2 billion people dying of starvation.

The right hon. Lady speaks with great passion and great authority on these matters. The question is whether she thinks that the awful scenario that she describes would be more or less likely if we did away with nuclear deterrents.

I will come on to suggest what the world community thinks about that. It is of course my opinion that we would be safer without nuclear weapons. If the hon. Gentleman were both to read the research on nuclear winters and the report of the accidents that have been recently published, he would realise that there is no safety in the possession of nuclear weapons, even if they are not used in anger.

It is instructive to look at how we view the world. We need to reflect on the deaths of those 17 people in Paris at the hands of terrorists. We were rightly outraged and right to mourn them, so how can it be that we are willing to contemplate the deaths of millions? Why do we have such moral certitude over the banning of chemical and biological weapons, land mines and cluster bombs but not nuclear weapons? It is also instructive to inquire how other countries and institutions view the nuclear weapon states such as Britain.

As always, the right hon. Lady is enormously courteous in giving way. It was discovered after the event that the Russians had been massively cheating on the 1972 biological weapons treaty. Therefore, it is the assurance of the underlying deterrent against other weapons of mass destruction that we have to worry about and be concerned with.

I am afraid that the hon. Gentleman does not make a coherent case. Chemical weapons have certainly been used in recent times—we do not know whether biological weapons have been used—which means that nuclear weapons did not act as a deterrent, so his argument is not sound.

The right hon. Lady makes a necessary contribution to this debate and she asks a very interesting question about the banning of other unacceptable weapons systems while we continue to possess nuclear weapons. But is it not the case that nuclear weapons represent, in the psychology of our global civilisation, an unacceptable threshold of use? Therefore, they have a deterrent effect because the release of one weapon could release many. I ask her this question: why, since the end of the second world war when nuclear weapons were first deployed, did war between the great powers end? Why was that the last world war? Could the possession of nuclear weapons have something to do with it?

I am afraid that the hon. Gentleman does not know his history. There have been hundreds of wars since that time and hundreds of thousands of people have died. Many of the wars were proxy wars between the superpowers, so his argument is completely invalid. If he argues that deterrence is so wonderful because the weapons are never used, then he has to ask: why have them at all? Let us get rid of them rather than posture and spend vast fortunes and create a situation in which, at the very least, accidents and misjudgments could happen. The point about luck is that eventually it runs out, and that could happen.

It is instructive to inquire how other countries and institutions view the nuclear weapon states. I had an opportunity to find that out last December when I attended a conference organised by the Austrian Government on the humanitarian effects of the use of nuclear weapons, to which the hon. Member for Moray (Angus Robertson) has already referred. Building on two previous meetings hosted by Norway and Mexico, this conference was attended by representatives of no fewer than 157 Governments. Most telling were the contributions of the International Red Cross and Red Crescent, the bodies on which the whole world depends, regardless of politics, in cases of natural disaster. Let me quote from their statement:

“Even though only a few states currently possess nuclear weapons, they are a concern to all states…They can only bring us to a catastrophic and irreversible scenario that no one wishes and to which no one can respond in any meaningful way.”

Their statement continues:

“All other weapons of mass destruction, namely chemical and biological weapons, have been banned. Nuclear weapons—which have far worse consequences than those weapons—must now be specifically prohibited and eliminated as a matter of urgency.”

I do not think that there is anyone who could not respect a statement from the Red Cross and the Red Crescent.

I am just about to finish.

After the conference, the Austrian Government issued a pledge in which they promised

“to identify and pursue effective measures to fill the legal gap for the prohibition…of nuclear weapons”.

About 40 countries have already signified their support for progressing towards an international treaty that could ban all nuclear weapons.

The renewal of Trident flies in the face of such international action and it must not be allowed to do so. The real threats to this country are cyber-warfare, terrorism, climate change and pandemics. We need all the resources we can muster to confront these threats and we cannot afford to squander billions of pounds on a weapons system that by general consent can never be used.

I declare an interest in that I am a trustee of VERTIC—the Verification Research, Training and Information Centre, a charity that carries out the verification of nuclear disarmament. I am also the vice-chairman of the all-party parliamentary group for the armed forces, with special responsibility for the Royal Marines and the Royal Navy. This is an issue about which I feel very strongly.

As you might know, Madam Deputy Speaker, on my election in 2010 I submitted a paper for the 2010 strategic defence and security review. I am preparing my contribution for the next SDSR in 2015, in which I argue that we should spend at least 2% of GDP on the defence of this country. I would also urge those in the Treasury, if they are listening, to take the cost of the nuclear deterrent out of the defence budget. I confirm my commitment to our retaining our nuclear deterrent because, in my opinion, it is the cornerstone of our membership of NATO and of our seat on the UN Security Council.

I represent Devonport, the only UK dockyard with a nuclear licence, so I can speak with some relevance about how my constituency is on the front line of defending our maritime interests. Nobody knows what the outcome of May’s general election will be, but the Scottish National party, the Greens and Plaid Cymru have all made it quite clear that they will not enter coalition with the Conservatives. According to The Independent on 15 December, the SNP, Plaid Cymru and the Greens, as their price for supporting the Labour party in a hung Parliament, would demand the scrapping of Britain’s nuclear weapons programme.

The Liberal Democrats appear still to be opposed to renewing Trident. Earlier today, I checked their website. That is an interesting thing to do and I encourage Members to do it. It clearly states:

“Britain’s nuclear deterrent, which consists of four Trident submarines, is out-dated and expensive. It is a relic of the Cold War and not up-to-date in 21st century Britain. Nowadays, most of our threats come from individual terrorist groups, not communist countries with nuclear weapons.

The Liberal Democrats are the only main party willing to face up to those facts.

The UK has four Trident submarines on constant patrol, which are nearing the end of their life. A decision needs to be made about what we do to replace them.

It would be extremely expensive and unnecessary to replace all four submarines, so we propose to replace some of the submarines instead. They would not be on constant patrol but could be deployed if the threat from a nuclear-armed country increased.

This would keep Britain safe while allowing us to move down the nuclear ladder in a realistic and credible way. While we cannot predict the future, making this first move on the road to international nuclear disarmament is the right thing to do.”

We either have deterrents or we do not. It is not a grey area, it is not a mishmash: we either have them or we do not. We cannot have a part-time deterrent, as it does not work. It is not part of the strategy.

That was what I was coming to. As my right hon. Friend the Secretary of State for Defence has repeatedly said, such an approach would mean that we would have only a part-time deterrent. We would depend on a part-time enemy. No doubt we could also go on holiday all the time.

May I commend to my hon. Friend and the whole House the lyrics of a song that was prevalent at the Liberal Democrats’ last conference, which came from their own side? Sadly, I have not committed all the verses to memory, but they were wonderful, and the chorus was, “We believe in a part-time submarine.” It was sung to the tune of “Yellow Submarine”, made famous by the Beatles.

I thank my hon. Friend for that.

Scrapping or even reducing the number of nuclear submarines would have a devastating impact on my constituency and on Plymouth’s travel-to-work economy and skills base. No SNP, Green or Plaid Cymru Members have talked about the importance of nuclear submarines to my constituency and I hope that my comments on Plymouth will be in accord with the views of the hon. Member for Plymouth, Moor View (Alison Seabeck), who is unable to comment as she sits on the Opposition Front Bench. In the past we have had a similar approach and I am sure that we will continue to do so. I hope that I and my hon. Friend the Member for South West Devon (Mr Streeter), my hon. and learned Friend the Member for Torridge and West Devon (Mr Cox), my hon. Friend the Member for South East Cornwall (Sheryll Murray) and the hon. Member for Plymouth, Moor View, all of whom have constituencies in the Plymouth travel-to-work area, speak with one voice on this issue, which involves Devonport’s future. I thank my hon. Friend the Minister again for the £2.6 billion of investment in the future of Devonport announced last September. That will secure 3,000 to 4,000 jobs over the next four years.

Retaining Britain’s nuclear deterrent, a strategic concept that seeks to prevent war, is a key element of and cornerstone in the defence of our country. It is a vital ingredient of our membership of NATO and of our relationship with the United States, which is our strongest ally, and it ensures our seat on the UN Security Council. It helps to prevent attacks from would-be aggressors and stops other countries using their nuclear arsenal to try to blackmail us. The United Kingdom is an island nation that is dependent on protecting its trade routes, which means that we need a strong Royal Navy.

Our ownership of this highly successful deterrent came about after the bombing of Hiroshima, which brought about the very dramatic final phase of world war two. I note that there has been no mention in the debate of Hiroshima, the event that ended the second world war. Like a slap in the face, it shocked the world with its catastrophic implications, which were so dramatic that no one has ever dared to push international conflicts to a point at which any country has used nuclear weapons again.

The nuclear deterrent has been Britain’s most effective insurance policy and it continues to play a significant role in maintaining peace throughout the world. Unpredictable countries such as Iran and North Korea, which are threatening to develop nuclear capabilities, make it vital that Britain retains its nuclear deterrent. It continues to act as a pressure point—conventional capabilities cannot and will not have the same deterrent effect as nuclear weapons. To quote the Prime Minister, it is the “ultimate weapon of defence”.

Indeed, the development of nuclear weapons since Hiroshima continues to have a significant impact on those veterans who were dispatched to Christmas Island, Montebello and Malden Island to take part in the tests that made the nuclear deterrent we are discussing today possible. I pay tribute to them and encourage the Government to try to look after those people. We must remember that we owe them a great debt of gratitude and it would be most helpful if my hon. Friend the Minister paid tribute to them when he winds up the debate.

For Plymouth, the deterrent is not just a defence weapon but a key part of our local economy, as well as of the national economy. It helps us retain our skills base, especially in Devonport, which is part of my constituency, and, of course, in Barrow-in-Furness. Devonport dockyard, which is responsible for refuelling and refitting our nuclear submarines, is a vital part of our local economy as more than 25,000 people in the Devonport travel-to-work area depend on defence for their livelihood. The mind-boggling announcement by the Liberal Democrats that the UK should move away from a continuous at-sea deterrent and reduce the number of submarines from four to three would have a devastating impact on my city’s economy. Their insistence that the maingate decision should be delayed until after 2015 has produced real uncertainty in our local economy.

If the ill-minded desire of the Liberal Democrats, the Scottish national party, Plaid Cymru and the Greens were to become reality, it could damage not only the livelihoods of 25,000 people but the skills base in a city with a low-skills and low-wage economy. It would damage the job prospects of those young people who are at the university technical college in Devonport, which is set to give youngsters an education that will eventually deliver a skilled work force who want to be employed in our dockyard. The measure would be most unhelpful.

A reduction in the number of nuclear submarines would mean less refitting work, and our highly skilled work force in the dockyard would have to move elsewhere in the country, which would also be problematic for the local economy. Given the importance of Devonport to the south-west economy and the defence of our nation, I find it extraordinary that the majority of the smaller parties in the House are doing everything they can to delay maingate for the Trident replacement. It is quite apparent that the future security of our country is going to be one of the bargaining tools that they can use in any negotiations that they have with Labour, should the result of the general election be a score draw, as happened in 2010.

Sadly, the leader of the Labour party has not said that the future of four nuclear submarines and a continuous at-sea deterrent is not up for negotiation in any potential coalition or supply and demand agreement. At least we now know that only an outright Conservative victory will ensure that our country will continue to play a significant part in global politics and that we have the necessary tools to defend ourselves. That is why I will continue to use the Royal Navy’s truly excellent toast from the Napoleonic wars: confusion to the enemy on this issue so that we can ensure that Drake’s drum can be put away for the next five years and we will not hear a drum beat for many a year yet.

May I say at the outset that I have never been a member of CND, and am never likely to be a member? I have always supported NATO, and I did so at a time when there was great controversy about NATO and its role in the cold war. I have always believed that NATO is the most successful mutual defence pact in history. It kept the peace in Europe for 50 years until the end of the cold war, and it gave rise to the American nuclear umbrella, which I support, because I have no ethical objection to nuclear weapons. Of course, I would prefer a world without them.

We have not had the pleasure and privilege of a Labour spokesperson contributing to the debate, and we all very much look forward to that. Will the hon. Gentleman tell me whether the Labour party will oppose the motion, or is it going to abstain? What is his Whip telling him to do?

I have not had the pleasure of being asked to be a Labour spokesperson, so I cannot answer that question. What I can tell the hon. Gentleman is that I will go into the same Lobby as him, and I shall explain why.

I have no ethical objections to nuclear capability or to nuclear weapons. As I said, NATO is the most successful mutual defence pact the world has ever seen. It has never attacked anyone, unlike the Warsaw pact, and it kept the peace in Europe for 50 years. I am one of the people who regret the change in strategy that resulted in NATO becoming the world’s policeman. That was dangerous, and it has put enormous strains on NATO, but it is still an effective mutual defence pact. I shall argue that that is how we get our security, rather than with the mythical idea that we have an independent nuclear deterrent. There are two myths.

I do not think that it is mythical. We have command and control. The management of some of the systems is based on the east coast of America when we change them, but command and control arrangements are entirely ours, so the deterrent is independent.

I am coming on to that. Let me deal with, in my opinion, myth No. 1. The UK has four nuclear submarines. Each can carry up to eight missiles, and each missile can carry up to five nuclear warheads. That is 40 nuclear weapons of the 17,000 that the Minister said are in existence. The UK does not own the missiles on its submarines. It leases Trident II D5 missiles from the United States, where they are made, maintained and tested. Our four submarines have to go to the American naval base in Georgia to have those missiles fitted. If Members like to believe that somehow that means that we are an independent nuclear power, so be it, but I would say that we are totally dependent on America. I do not oppose our being dependent in defence on America; I am a strong supporter of the Atlantic alliance, but I am not a supporter of mythology.

If the United States withdrew co-operation for the maintenance of our nuclear deterrent, the fact is that the capabilities with which they provide us have a long lead time, so we would have time to develop our own indigenous capacity to provide those capabilities. There is no point in our doing so while the US is happy to share the costs with us and help us to provide a cheaper, better-value nuclear deterrent.

I take note of what the hon. Gentleman has said, but we are where we are. We acquired these weapons from the USA.

The hon. Gentleman, as always, is being very thoughtful on the subject. What he has said is true: the missile bodies are from a common pool that we share with the Americans. What makes a weapon system independent is not who manufactures it, and not who co-owns it—it is who is in a position to launch it if the need arises. There would be an enormous lead time to any withdrawal of the sort of co-operation that we need from America, so if there were any attempt at a surprise attack on the UK, because America does not have its finger on our nuclear trigger, the independent system is exactly that.

The hon. Gentleman is knowledgeable about defence issues, but he will recognise that one of NATO’s founding beliefs was, and still is, that an attack on one is an attack on all. The view that the country could be subject to a nuclear attack without the response of the American nuclear umbrella is, in my opinion, inconceivable, and is completely contrary to what NATO is and why it has been successful.

Is there not a paradox? If we reduced the nuclear arsenals so that only the United States and NATO possessed one we would have the problem that an attack on one would be a response by one. The absence of diversity would make the NATO structure much less resilient.

I have consistently said throughout this speech that I believe our security is based on our membership of NATO. I strongly support NATO and always have, and I strongly support the basis on which NATO was set up, which is that an attack on one is an attack on all. The idea that just because one country, America, which provides the nuclear umbrella, has far, far more nuclear capability than our 40 missiles or than the French nuclear capability—

I am trying to understand this more broadly, strategically speaking. Is this not in danger of being an argument simply that the whole of NATO should be freeloading on the United States?

The hon. Gentleman says that we are freeloading on the United States. In fact, NATO has taken part, I think wrongly, in actions to be the world’s policeman where its component forces, not just Americans but British and other participants, have gone into theatres of operations as part of the collective NATO force. I would argue that we would be far better off maintaining and developing our conventional forces. As the hon. Gentleman knows, there have been incidents where British troops have been killed in the middle east because of a lack of body armour and because some of our machinery has not been fit for purpose. If it is a choice between modernising and maintaining good conventional forces, properly equipped to do the job, and the mythology of an independent nuclear deterrent, I would most certainly go for the conventional forces.

There is at the moment quite a debate across the United States about freeloading, with a high degree of concern that about 70% of the costs of NATO are paid for by the US. Is my hon. Friend seriously suggesting that we should front-load further costs and renege on our own responsibilities in relation to the nuclear deterrent? I honestly do not think we can say that and hold our heads high in the world. In relation to the body armour, that was an issue of slow procurement, not cost.

My hon. Friend is suggesting that if, all of a sudden, we gave up our 40 missiles, America would rush in to create 40 extra missiles to compensate for those that we are not going to have. The Americans have expressed regret to us about cuts that we have made in our conventional forces; they would like us to do more in that regard. I would strongly argue that that is a much greater priority than the myth of our so-called independent nuclear deterrent.

May I make some progress, as I have been generous in giving way?

The hon. Member for Plymouth, Sutton and Devonport (Oliver Colvile) said that it is absolutely vital that we maintain our nuclear capability because otherwise our position as a member of the United Nations Security Council could be endangered. When the UN was set up in 1947 or 1948 there was only one nuclear power, and that was America. The other five countries that ended up on the Security Council were not nuclear countries; they were the victors of the second world war. If, as he suggests, a country has to have a nuclear capability in order to become a member of the Security Council, that does not say much for our championing, quite rightly, the aspirations of Japan, as a non-nuclear power, to become a member, or Germany’s desire to become a member. If that were a criterion, the two obvious applicants would be Israel and North Korea.

The hon. Gentleman refers to the Americans developing their nuclear capability. Does he not accept that the Americans did that, in very large measure, in consultation and in conjunction with the research carried out here in the United Kingdom?

The hon. Gentleman has made his point, and we are where we are. I can only say again that I believe that committing £100 billion to renewing our nuclear capability is not money well spent. I have sat here with my hon. Friends watching Defence Ministers come to the Dispatch Box to announce the cutting of this regiment, the cutting of that regiment, the abolition of the other regiment. Those are massive cuts in a defence capability that should have far greater priority than our so-called independent nuclear deterrent.

The need for our security is of course absolute. We have to ensure that we are protected from attack from without or within. I believe that our security is best achieved through collective action through NATO with other countries, and I believe very strongly in our membership. I also believe that the greatest threat to this country comes not from other countries but from groups, some of which operate outside this country but some of which operate within this country. In a choice between spending money on conventional weapons and improving our internal security or committing £100 billion to a mythical so-called independent deterrent, I know which I would choose. That is why I will be voting against my party and in favour of the motion.

The decision to procure the existing Trident nuclear system was taken in 1980. My starting point is that the world has changed a very great deal since then. Back then, we were at the height of the cold war. We had a known nuclear adversary that had the capability to strike us and had stated its willingness, if provoked, to do so. We, in turn, felt that it was absolutely essential that we had the ability to respond at a moment’s notice. Thus it was that we concluded that we needed an inter-continental ballistic missile capable of being launched at a moment’s notice, and that because we did not know when our adversary would attack, we would sustain a patrol 24 hours a day, seven days a week, 365 days a year. There was logic in that position.

But, as I say, the world has changed. The cold war is over. The iron curtain has come down. The Soviet Union, which was our known adversary, no longer exists. In 1994, Britain and Russia de-targeted each other and changed their policy to say that we were not nuclear adversaries of each other. Yet nothing changed: since that time, we have continued with 24/7 patrolling. I join the Secretary of State in saluting those who have been involved in sustaining that for all that time. The Royal Navy and all those at the Faslane base and in the supply and support chains have mounted a gargantuan effort to keep continuous at-sea deterrence going, and they deserve great praise for that. It has been at considerable human cost and very substantial financial cost, but it is very much harder to discern quite what practical utility it is fulfilling in 2015 when we do not have a known nuclear adversary.

I am loth to interrupt the hon. Gentleman because he is making a very good case, but does not he agree that Trident is a weapons system designed for the Brezhnevs of the world, not the bin Ladens and the current threat?

As I have said, it was something that we calibrated to be our need in 1980. If one casts one’s mind back to 1980, one will see that our conventional defences were very much greater than they are today. The scale of the nuclear deterrent that we mounted at that time was a relatively small proportion of a large defence, but what we are considering now, as we look forward to the next 30 or 40 years, is a much greater proportion of a much smaller defence because of the succession of cuts that have been made since then.

The hon. Gentleman says that we can look forward in anticipation of certain types of dangers but that there is no known nuclear threat. May I remind him of how suddenly the crisis in Ukraine blew up; if it were to develop, as it could, into all-out war that then spilled over into Lithuania or Poland, which are NATO members, nuclear deterrents might become very relevant indeed, very quickly.

I will come on to talk about the implications and the consequences of using nuclear weapons, but—although the hon. Gentleman is right to say that the security situation in and around Ukraine deteriorated rapidly—I do not accept for one moment that anything that has happened there makes the prospect of nuclear conflict between ourselves and Russia any more likely than it was before all that started.

I remind the hon. Gentleman of the following words:

“I admit to some miscalculations about Russia. I did not calculate how the collective mood of Russia was so ready to respond to a dominant and ruthless leadership…Nor did I expect that the perestroika and glasnost that we welcomed so enthusiastically in this country and elsewhere would become so despised at home in Russia.”—[Official Report, 18 March 2014; Vol. 577, c. 670.]

Those were the words of his colleague, the right hon. and learned Member for North East Fife (Sir Menzies Campbell). Why is the hon. Gentleman so confident that he can predict the future when the right hon. and learned Gentleman has admitted that he was wrong?

I am making absolutely no attempt to predict the future; I am talking about the threat that I believe we face now at this point in time. For another nation sate to be taken seriously as a nuclear adversary, it needs a combination of capability and intent. Although it is certainly the case that the Russians and many others have the capability to strike us with a nuclear weapon, I do not believe for one moment that they have the intent to do so. If things should deteriorate in the future, that is a different position, but I do not believe that we face such a threat.

I am going to make some progress and I will take another intervention in a little while.

Our defences have seen round after round of cuts as the financial situation has deteriorated, and later this year we face the gloomy prospect of the whole thing happening all over again. Whatever the outcome of the election, there will be a strategic defence and security review this summer and a comprehensive spending review this autumn.

The Secretary of State dismissed the cost figures offered by the hon. Member for Moray (Angus Robertson), who opened the debate for the SNP, but I readily recognise those figures. It is a fact that if we go ahead and build four submarines, they will cost us between £25 billion and £30 billion. It is a fact that running the nuclear deterrent currently costs us £2.9 billion a year, and if we do that for another 30 or 40 years the cost will multiply. Whatever the outcome, at some point we will have to decommission it all at the end, so I would have thought that £100 billion is the very least it would cost. I would take a private guess that the quantum would in fact be well in excess of that figure, but I certainly recognise it as a starting point.

On the basic maths, if the figure of £2.9 billion is right and, as CND’s own estimates say, the £100 billion figure is stretched over the whole lifetime of 50-plus years, could the hon. Gentleman tell me what is £2.9 billion times 50?

I was taking the lifetime of the submarines as being more like 25 to 30 years. If we operate them for 25 years at almost £3 billion, that would take us into the realms of £75 billion plus the building and decommissioning costs, which would certainly take us over £100 billion very quickly indeed. I would have thought that, in reality, it will cost a great deal more than that.

We know that the national deficit remains a serious problem and we do not hear from any of the political parties—mine or anybody else’s—that defence will be insulated or protected from a tough comprehensive spending review later this year. If defence were to face another cut comparable to that which it took in 2010, which seems entirely possible, the proportion of our gross domestic product that we spend on defence, which is already destined to go below 2% next year, will make rapid headway down towards 1.5%.

We know, however, that on the table for discussion in this summer’s SDSR is a whole series of big procurement projects. The two new aircraft carriers are due to have joint strike fighter craft flying off them—we do not know how much their unit cost will be or how many of them we will be able to afford. The Type 26 frigate is due to be built in the next few years, but it is very difficult to know how much that will cost. We need more helicopters and more intelligence, surveillance, target acquisition and reconnaissance assets. We need another generation of remotely piloted aircraft. The existing amphibious shipping is due to become redundant in the latter part of this decade and will need replacing if we are going to sustain that capability. The Army’s vehicle crisis remains unresolved after the collapse of most of the future rapid effect system programme.

All those things will be on the table and wrestled over in agony this summer. In addition, paper exercises are already being done looking at what an Army of just 60,000 would look like, because of the financial crunch that the Department will face. Yet, for some reason, keeping a nuclear deterrent going at the level we thought necessary at the height of the cold war in 1980 gets an automatic bye and is assumed to be beyond debate. Nobody even wants to put it on the table and debate it alongside those other things that are there to mitigate the dangers that our own security assessment said in 2010 are first-league threats that we face here and now.

The hon. Gentleman has spoken fluently about the kit, but I still do not understand the strategic vision. What threats does he think we face? Why does he think that the frigates are important and that nuclear weapons are not for deterring that threat? What kind of intent does he think Russia has? What kind of obligations does he believe we have for NATO, and why are nuclear weapons irrelevant to that obligation?

The 2010 national security strategy identified the primary threats faced by the United Kingdom. Personally, I think it was correct in identifying the threat from international terrorism, cyber-attack, international crime, the security consequences of the sudden mass migrations of peoples, and pandemics as a result of climate change. All those are very real threats that we face, and they are probably greater than the threat we face from direct state-on-state warfare. We see every day that our armed forces—through, for example, the work they perform off the African coast countering piracy and in the Caribbean countering narcotics—are very flexible and capable of dealing with this wide and diverse range of threats. It is actually maintaining a broad spectrum of capabilities to deal with such diverse situations and the willingness to use them that secures us our place at the United Nations Security Council, not the fact that we happen to be a nuclear state. In any case, we can change the composition of the United Nations Security Council only by unanimity, and there is no reason why the UK should agree to give up its seat.

Does the hon. Gentleman recall that representatives from NATO came to my constituency last year? I was very happy to welcome them. Of the 28 countries, 25 are non-nuclear states, and they found no difficulty walking with their heads held high.

It is certainly true that very few NATO states possess nuclear weapons, although a few have them on their soil. Other Members have spoken about the nuclear umbrella, but none of us knows how real it is, and let us hope that it is never pushed to the test.

We are asked to focus our minds on whether we should proceed with a replacement programme in 2016. It is not of course the Trident missile that needs replacing, but, as other hon. Members have said, the submarines. I believe that we should be willing to build some more submarines at this time, but I shall add some riders in a moment.

The hon. Gentleman is being very good speaking his mind, but I am somewhat confused. Will he vote for or against the motion?

If the hon. Gentleman bears with me, I shall do my best to explain my position and where I am coming from.

I profoundly agree that we should not allow the Barrow submarine-building capability to fall apart—if we do not place such orders at that shipyard in the next few years, it will be necessary to give it other contracts—but I do not support the construction of submarines whose sole purpose and capability is to carry a nuclear weapon, thus committing us to a £30 billion investment programme with but one purpose and forcing us to be a nuclear power for the next 30 and 40 years unless we are prepared to write off a capital investment of that scale.

The United States has used some of its Ohio class submarines for quite different purposes. The US has developed a means of firing conventional weapons through their missile tubes, and it has used those submarines in a tactical role and in support of special forces operations. To my mind, it is certainly the case that if we are to build new submarines—I think we should, for the reasons I have given—we must ensure that they are capable of performing other functions, as the United States has done with its large submarines.

The hon. Gentleman is being terribly generous in giving way. The fact is that his party’s policy, strange though it is, is to build another two Trident submarines, however they are deployed. Does it not follow logically, given the terms of the motion, that the hon. Gentleman and his party should vote with us against it?

No, because that would imply that we were in favour of a full-scale, like-for-like replacement of the Trident programme. [Interruption.] If one is going to be pedantic, the motion refers to a missile system that is not due for replacement for some years. In fact, what needs to be decided in the next year or so is whether we shall build new submarines. I think we should, but if we make such an investment, it is essential that the submarines are capable of performing other functions. I do not believe that it makes any sense whatever for us to sail the high seas 24/7, waving weapons of mass destruction at the rest of the world, because we thought it was necessary in 1980 or because we would be left looking embarrassed if we did not make that £30 billion investment.

The Defence Secretary seemed to suggest that to adopt any deployment posture other than continuous at-sea deterrence was somehow risible and laughable, but many sensible studies by serious people have looked at a ladder of different postures for the UK to take. My belief is that we should for the time being retain the components of a nuclear deterrent—the warhead, and the ability to look after it; the missile, and the arrangement with the Americans; and the submarines capable of firing a nuclear weapon—and maintain a highly skilled work force who are regularly exercised in how to put back together the deterrent’s components. NATO air-based nuclear systems in eastern Europe operate on the same basis of a well-exercised drill to put the pieces of the deterrent together if it is thought necessary.

I will give way to the hon. Gentleman in a moment, as I said I would.

In this day and age, it does not make sense for us to go out to sea armed with nuclear weapons and on patrol when we do not believe, on our own assessment, that we face a primary threat. I do not believe that we have a nuclear adversary at this time, but in future we might reach a different conclusion and believe that the international security situation had so deteriorated that we faced a nuclear adversary. For that purpose, it seems to me to make sense to keep the component parts of the nuclear deterrent and the ability to put them together again should we ever need it.

I do not at all accept that that would be a part-time deterrent. I do not believe that the Royal Air Force—or the Army or the Navy for that matter—represents a deterrent to a potential enemy only when on patrol. The fact that it is known to have the capabilities it has is in itself a deterrent. If one wanted to be pedantic and to cling to the belief that it has a deterrent effect only when on patrol, let me make it perfectly clear that I am proposing patrols not for part of the time but for none of the time. I propose that we simply retain nuclear capability as a contingency against a future situation where we made an assessment that we needed to operate a patrol.

When I studied the strategy of deterrence, it was predicated on the fact that a country deters by being ready to strike back, and that deterrence therefore works. We cannot deter by saying, “Well, in a couple of weeks’ time, we might actually fire something at you,” or whatever. The whole point of deterrence is that we do not want anything to happen, and it works because everyone is frightened to do anything.

I do not think that I have made my point quite clear to the hon. Gentleman. I do not believe that we have a nuclear adversary, but I am saying that we should keep the component parts of the deterrent for the time being so that if in future we concluded that we did have such an adversary, we could resume patrols. I am absolutely with him in saying that for something to have a deterrent effect, it needs to be mobilised and deployed in a timely matter, but I simply do not accept his proposition that—out of the blue, out of nowhere—an adversary will pop up who wishes to do us irreparable harm and to take the global consequences of doing so.

The hon. Gentleman is very kind to give way. He was a Minister at the time of the strategic defence and security review, and he signed up to it. I did not agree with many parts of that review, but it made it very plain that this country has nuclear opponents and that there is a nuclear threat. Has his opinion therefore changed not just since the 1980s but since 2010, because that is what he is saying?

I remind the hon. Lady that the national security strategy identified such a nuclear attack as a second level threat. I believe that we have potential nuclear adversaries, but I do not believe that we have actual nuclear adversaries at the moment. To be an actual adversary requires a combination of capability and intent. I can see plenty of countries with the capability but none with the intent, and countries that may have an intent to launch a nuclear weapon at us in future are still a considerable way away from having such a capability. If any of that should change, and if any future Government should arrive at a different calculation and believe there was an enemy with both capability and intent, they would need to revisit our posture.

Trident should be retained on a flexible basis that can be ramped up or down according to our reading of the security situation, which is exactly how we approach all our other military capability. The rest of our military capability is not kept on constant patrol on the basis that that is the only point at which it has any deterrent effect; it is kept at different levels of readiness, according to our assessment of the particular threat that it is designed to mitigate.

Does the hon. Gentleman agree that the one scenario in which there could be an instant attack, without the build-up and norms of international discussions or whatever, would be a terrorist nuclear attack, not state sponsored but by something like ISIS? In those circumstances, does he agree that our nuclear weapons system is completely useless and does not deter?

The right hon. Lady makes a good point. If a threat emerges from nowhere, it will be either at the hands of terrorists or a by rogue state sponsored by terrorists, against which a conventional state-on-state nuclear deterrent of the sort that we have would have absolutely no value or purpose. It is important to remember that we have moral and legal obligations to try to bring about global nuclear disarmament, and with one notable exception I hope that all Members of the House believe that that is a desirable objective.

In 1968 the non-proliferation treaty was in effect a pact between the nuclear states that were going to use their best endeavours to negotiate away their weapons and the rest of the world that agreed not to develop nuclear programmes. In terms of non-proliferation the treaty has been moderately successful, but it has made astonishingly little progress on disarmament. Very few signatories to that treaty can have imagined that by 2015 so little progress would have been made. Things are stirring and changing, and the British Government need to wake up to that. More than 150 nation states have attended international conferences and considered in detail and depth the humanitarian consequences of using nuclear weapons.

The hon. Gentleman is being very generous with his time, but his remarks are taking Liberal Democrat policy into a new out-of-body, out-of-mind, out-of-space dimension. Some points are unclear from his remarks, and I would be grateful if he would be clear about them before he concludes his speech. I think he said that his party’s policy now is to have all the components and capability delivery of a nuclear system but with none of them joined up, and therefore with none capable of being trained and exercised in a way that—as he will know from his time as Minister for the armed forces—takes months if not years to deliver. There would therefore be no deterrent capability at all: not a part-time deterrent, but no deterrent. How will he vote tonight?

I invite the Minister to look at how the NATO air-based nuclear capability in eastern Europe operates, because what I am describing is a precise replica of what goes on there. That capability is not on constant patrol or constantly armed; it exists in its component parts, and there is a well-rehearsed exercise for mobilising it and putting it together. Does that have a deterrent impact? I believe it does. If anybody intends to strike faster than that capability can be put together again perhaps it would not, but who is going to do that?

This brings us to the humanitarian consequences of nuclear weapons, which I think are singularly under-perceived in this country and many others, although that is changing fast. The participation of many Governments at conferences—the first in Oslo, the second in Mexico, and the most recent in Vienna—is bringing a far greater degree of awareness around the globe of the impact of using nuclear weapons. I do not believe that the public who have come of age since 1983—the last time we had a meaningful national debate about our nuclear deterrent—understand what the consequences of unleashing the payload of one of our Vanguard submarines, armed with Trident missiles, would constitute.

If one of our submarines were to unleash its payload against, for instance, Moscow—those were the traditional criteria on which we based our capability—I think that some people in this country, possibly even in the House, labour under the misapprehension that the consequences would be pretty grim for people in Moscow and perhaps not very clever for those a few hundred miles around. In reality, if we were to unleash the payload of one of our submarines, the consequences would be global and felt for at least a decade, and at least a billion people would be at risk of dying. The more widely that is understood, the more inconceivable it is that any sane person could ever push the button, and the more widely that is understood, the less deterrent effect the possession of this great paraphernalia comes to have.

Does the hon. Gentleman recognise that although the British deterrent is used all the time to deter, the only scenario in which it is conceivable that it would be fired would be in retaliation for someone having fired a nuclear salvo against us? Therefore, all the consequences that he mentions would already have happened, and the only question would be whether it would be worthwhile replying under those terrible circumstances. The purpose is to prevent anyone firing the weapons in the first place, and that is how we avoid the environmental consequences.

I am surprised to hear the hon. Gentleman make that case, because I believe he is right. After such a volley had been unleashed against us, no earthly good could possibly be done by firing one back in retaliation, and the more we think our way through that, the more pointless the whole exercise becomes. Indeed, it is not simply pointless, but the rest of the world is becoming increasingly irate about the complacency of those who continue to have these weapons while saying to everybody else, “You’ve got no right to them, but we’re all right, Jack. We’re going to have them.” That situation is not sustainable for much longer, and it was regrettable that the P5 boycotted the first two conferences. It is much to be welcomed that there was British, American and even Chinese attendance at the most recent conference, because I predict an increasing clamour from other countries around the globe for the nuclear states to begin taking steps down the nuclear ladder. Traditionally that has been done by reducing the stockpile of warheads, but today I have attempted to explain that there are other ways of doing that, and the posture we strike and the way we use our capabilities has an important part to play. It is not 1980 and we do not face the threats we thought we faced then; it is a very different world and there is a way for us to begin climbing down the nuclear ladder. We have the opportunity to do that, and we should take that opportunity and get on with it.

It is a treat to follow the hon. Member for North Devon (Sir Nick Harvey), and the House should take a moment to appreciate his tenacity. This is a man who at the last election spearheaded his party’s drive not to have deterrent successor submarines at all, but to have an entirely new form—a mini-deterrent, with adapted Astute submarines and nuclear-tipped cruise missiles. The Liberal Democrats were so sure of that policy that they put it before the electorate. It was not successful, but they retained it. As Minister, the hon. Gentleman was so determined that he persuaded the Government to fund the Trident alternatives review. That review took 18 months or two years to examine that option exhaustively, finally to conclude what we had been saying all along, which is that the policy was complete nonsense and would cost even more than the current system and be far less efficient.

The hon. Gentleman is not deterred by that. In the manner of a child jumping from sandcastle to sandcastle as the tide comes in, he seeks to find new ways to differentiate himself from the Opposition while never saying the words, after his exhaustive speech, that he is a unilateralist and his party is a unilateralist party. There is an absurdity—I think I have it right—to having not a part-time deterrent, but a no-time, or IKEA, deterrent that he could put together at some point. IKEA furniture can be difficult to assemble, but it does not take the months or years that his proposal would take. In the meantime, would we put glass in the submarines so they can become public viewing vessels? Could they carry grain, so that they could become underwater famine relief vessels, which is one of the more famous suggestions from the unilateralist CND members in my constituency? What is it? Tell the House, or is he going to leave this policy until the election to reveal it?

Goodness! If the hon. Gentleman wants to tell me that firing grain out of the torpedo tubes of the successor to Vanguard-class submarines is an effective use of public money, then he should go ahead. I will come on to his policy in a little while, if he does not mind.

I am greatly enjoying the hon. Gentleman’s speech. Coming back to the real world, is it not the case that the need to have a continuous at-sea deterrent follows directly from the fact that we have a minimum strategic deterrent? We only have four submarines. At any one time only one or two of them can use or fire their missiles—they use them all the time to deter—but the fact is that if we did not have one continuously at sea, a surprise attack would wipe out the whole capacity.

That is exactly right, which is why a part-time deterrent is no real deterrent at all. The point of having submarines that are continuously at sea means that they are, in effect, completely invulnerable. If, in a future nightmare scenario, the UK was seriously threatened by a nuclear attack, any potential nuclear adversary would know that they could not fire without being fired on. Even if they flattened the UK, they would always face the counter-strike. That is why it is a genuine deterrent and makes a nuclear attack less likely.

Was my hon. Friend not surprised to hear the hon. Member for North Devon (Sir Nick Harvey) say that his strategy is to try to acquire a nuclear weapon if it turned out we might need one? If someone fired on us it would be pointless responding by then. Potential adversaries of Britain would know that if they fired at a Liberal Democrat Government our response would be too late.

Exactly. The fact is that the hon. Gentleman does not believe it. He and his party should come clean that they are unilateralists and stop this charade of ever-new inventive fantastical solutions.

Does my hon. Friend think that the world is a safer place since 1980? North Korea and Russia have increased their arsenals, Pakistan’s arsenal has grown exponentially and Iran is trying to develop a nuclear capability. Are we actually safer since 1980?

My hon. Friend is absolutely right. The global situation is profoundly unstable. Whether or not there is a nuclear adversary precisely at this moment, we simply cannot say what will be the case in the next 20, 30 or 40 years. That is the decision we are making now: what threats we will face while other countries are increasing, rather than decreasing, their arsenals.

Labour is proud of its record on non-proliferation. My right hon. Friend the Member for Derby South (Margaret Beckett) was the Labour Foreign Secretary who committed the UK to a “global zero”—a world completely free from nuclear weapons. Britain was the first nuclear state in the world to sign up, before President Obama, before Russia—although it has clearly reneged on what it said—and, to the best of my knowledge, before either of the parties who have proposed the motion. They were busy thinking small, as is their wont. They were telling Scots that the answer to this issue was to expel nuclear submarines a couple of hundred miles south of the border—they are not coming to Barrow, by the way. They did that while having the cheek—I am not sure whether this is parliamentary language or not, Madam Deputy Speaker—to have the unbridled hypocrisy to say that nuclear weapons were grotesque and inhuman, but that they wished an independent Scotland to remain part of the specifically nuclear alliance of NATO.

I realise that, as the hon. Gentleman represents Barrow and Furness, he might have a slightly different answer to this question from other hon. Members, but at what point and at what cost does this weapon system cease to be a proper value-for-money decision for the United Kingdom? How much of the defence budget does it need to take before he would say, “Actually, we are better off investing in other weapon systems that are much, much more likely to be used”? What would his number be?

I will come on to figures later; I will make some progress first.

We will not insult people by saying that Trident is effectively fine as long as it is not coloured tartan. We are a party whose ambition is big. We have acted by reducing stockpiles and reducing to a single nuclear platform the minimum credible independent deterrent that it is responsible to maintain while others hold a threat that one day could be used to blackmail the United Kingdom. We led the world on “global zero” and we will lead again in government. Britain is an outward-looking country that shoulders its responsibilities. It will make genuine progress through multilateral negotiation, not futile unilateral gestures.

Labour is not a unilateralist party. I was at a CND “ban the bomb” demonstration at RAF Molesworth. I think it was in 1984 and I was aged five. If my mum will forgive me, I appreciate the fruit gums she gave me on that day but we are not going back to those days—we have moved on as a party. I listened carefully to my right hon. Friend the Member for Lewisham, Deptford (Dame Joan Ruddock), who has had to leave for a constituency engagement, but I was left questioning her opening statement. She called herself a multilateralist, but scrapping the programme to replace the ageing Vanguard-class deterrent submarines is tantamount to unilateral disarmament—not today, but a decade or so hence, once the Vanguard-class submarines are no longer seaworthy. As a result of the delays in bringing their successor into service, they are now projected to be the longest-serving submarines in the history of the Royal Navy, but they cannot go on for ever. At that point, we would lose our nuclear capability for ever, yet we cannot possibly know what threats we will face in decades hence. Not only would it put our security at risk, but for any genuine multilateralist, it would be a missed opportunity to encourage other countries and bind them into a deal that makes genuine progress across the world.

The construction taking place in my constituency, and in all parts of the UK, is among the most highly skilled, cutting-edge engineering in the world. We cannot just put these submarines on hold and then pick them up when they might come in handy some years down the track. While a “global zero” remains beyond the horizon, we will finish the programme of renewal that we started in government but which this Administration have delayed to the point that there is precious little contingency left.

The investment announced is significant, but the £100 billion is highly flimsy at best. We do not accept the figure, but—imagining that we did—let me put it into the context of overall UK Government spending, on current levels, over those 50-plus years, a time period that never makes it on to CND posters. According to my office’s estimate, all things being equal, Government spending over those 50 years will be £35,700 billion, which I am told is £3.7 quadrillion—not a number I have used before. Within that, pensions would account for £7,160 billion, and health for £6,475 billion—I used to work for my right hon. Friend the Member for Kirkcaldy and Cowdenbeath (Mr Brown), but not even he would use such figures. Education would account for £4,510 billion, and conventional defence for £2,115 billion. Over that period, the £100 billion figure does not seem quite the show-stopper unilateralists would have us believe.

I will not. I have given way once, and I want others to speak.

With money so tight, my right hon. Friend the Member for Doncaster North (Edward Miliband) understandably ordered his defence team to re-examine the case for renewal and the most cost-effective way of maintaining the minimum credible deterrent, to which we have always been committed, and it concluded that the submarine- based, strategic, continuously at-sea system remained overwhelmingly the most appropriate system for the UK, and that the most cost-effective way to deliver it was to continue with the successor submarine-building programme, which we began in government and will be voted on in the next Parliament.

It is for the nationalists to explain why they are seeking to prioritise unilateral disarmament by making it, as far as I understand it, their one red line in any future coalition talks—they would prioritise it over all the pressing issues of health, jobs, education and the economy that matter to the people of Scotland and Wales. It is also for them to say how their stance fits with their desire to remain a member of NATO. But Labour’s view is settled. The Leader of the Opposition will never accept an irresponsible deal that trades the nuclear security of future generations in a deeply uncertain world for nationalist support to enter Downing street. We will carry on campaigning for a Labour majority. Plaid Cymru and the SNP can dream on.

It is a great privilege to follow the hon. Member for Barrow and Furness (John Woodcock), who gave an extremely eloquent, entertaining and serious speech.

I will try to speak briefly. The great challenge here is to try to work out, after nearly 60 or 70 years of this debate, what new there is to say. The huge ethical issues that have been raised by Opposition members and the huge strategic issues that have been raised on this side of the House have been gone through again and again.

The one thing we should perhaps say is that, at the beginning of the 21st century, certain kinds of argument should no longer be relevant. The first argument that I do not believe we should be having is fundamentally an argument about economics. This is a large question. As was pointed out by Opposition Members, it is a question of Armageddon. It is question of deep, deep strategy. This is the fifth-largest economy in the world and we should not be making the decision on whether to keep nuclear weapons on the basis of either the belief that we could save some money by cutting them or alternatively the belief that we should retain them in order to keep some jobs in a marginal constituency. It is much more important than that.

What can we say? The first thing that we notice is that the nature of deterrence and the threats that we face have changed. The threats that we are facing now, particularly posed by Russia in Ukraine, which has been raised again and again, are not exactly the same as the kind of threats raised by the Soviet Union. I say absolutely straight out that I will be voting in favour of the retention of the Trident nuclear deterrent. It is a very important thing for us to do. But I have enormous respect for the people on the Opposition Benches who have anxieties about it, and it is to them that I want to address a few short remarks.

The history of the last 30 years, unfortunately, has shown that the kind of arguments made by people in favour of nuclear disarmament were, in the end—although well intentioned and frequently led by impressive intellectuals, bishops and scholars—proved wrong. In the end, it turned out that the people who were characterised as Dr Strangelove—the people written off as irrational and macho—had a better understanding of the mentality of Stalin and a better idea of how to protect western Europe. They should be thanked for the work they did, which contributed in no small way to ensuring that, today, we have had 70 years of the greatest and most productive and prosperous period of peace in Europe conceivable. We should also thank the Labour party for its contribution to the setting up of NATO and the commitment it has made to the nuclear deterrent since the second world war. We should continue to work together on this.

But the threat that we now face is a different one. We do not know what Putin is doing and before we decide how to deter him, we need to work out what the threat is. Is he intending to use nuclear weapons? We have noticed, for example, that he has been investing heavily in his tactical nuclear arsenal. He has also committed a great deal of money towards modernising his nuclear arsenal. He has been running exercises recently, including the deployment of a nuclear bomber to Venezuela. At the same time, the activities in which he is engaged, and which have been laid out by his chief of staff Gerasimov, are all arranged around the idea of ambiguous warfare, almost at the very opposite end of the spectrum from nuclear war; the use of special forces, intelligence operatives and cyber-warfare to create a situation such as in Donetsk where he continues to be able to try to claim deniability while putting Russian special forces and Russian weapons in on the ground. The question for us in coming up with a deterrent is how we deal with that threat.

What does the United States do to protect NATO? What is the United Kingdom prepared to do to protect NATO? Listening to the debate, I am not clear—I would be interested to hear what the shadow Spokesman says on this—as to what Britain is proposing to do with our nuclear weapons if Russia were to attack a Baltic state. We knew what we were proposing to do in the 1980s. The basic concept of the tripwire was that we had forces on the ground and were the Soviet Union to attack those forces, nuclear weapons would be fired at Moscow. In this debate there now seems to be some ambiguity. Are British nuclear weapons used only to defend British soil, or would they be used to defend the Baltic?

Is not the question: what will America do if there is an attack on the Baltic states from Russia? Our involvement in this is peripheral. We do not provide a deterrent; America does. We are clinging to this virility symbol as a gesture of our old national pride when it is not relevant. The whole point of multilateral disarmament is to reduce the number of nations with nuclear weapons down to two. By possessing them we are encouraging other nations to acquire them.

The hon. Gentleman makes a very good point, but I think the fundamental nature of our disagreement is going to be about our whole relationship to the NATO structure and the kind of role we wish to play within it. Although the hon. Gentleman is speaking very eloquently about nuclear weapons, I suspect he would also disagree with many Government Members about conventional weapons, and the role we generally play in protecting countries like the Baltic states against attacks from Russia.

If the hon. Gentleman wishes to intervene again, I would be very interested to hear what he proposes Britain should do to defend the Baltic states against such an attack.

I know the Baltic states very well: I visited them four times in the ’80s and ’90s. I am not suggesting that we pretend some fantasy nuclear war is going to take place with us as the main participant. Where we have been successful is in humanitarian interventions in places like East Timor and Sierra Leone. Where we have failed is where we have gone into Iraq and Afghanistan with all guns blazing. We are good at humanitarian intervention and that is where our money should be invested.

With respect, as I suspected, the hon. Gentleman is focused on issues like East Timor and humanitarian intervention which have very little to do with the question of NATO. This whole idea of an attack on one being an attack on all is fundamentally predicated on the idea of deterrence. It is fundamentally predicated on the idea that we in the UK, as a major member of NATO, would protect these states if they were attacked, and my suspicion is that the hon. Gentleman has no strategy whatsoever on how to defend them. Giving up on the nuclear weapon is simply a symbol from the hon. Gentleman—a virility symbol, perhaps—of actually giving up in general on our obligations to protect NATO states. If I have misunderstood, I am very happy to take another intervention.

The hon. Gentleman is being very generous. If he went to Tallinn or Vilnius and asked the people there who they would look to to defend them if Russia attacked, they would say they look to America, not us.

We can, of course, agree with the hon. Gentleman on that. That is true. One of the questions is working out what Britain is going to do, but of course the biggest question for Vladimir Putin is what the United States is going to do. But the reason why these questions, and the uncertainty around them, are relevant is that Vladimir Putin’s decisions on whether to use ambiguous warfare, conventional troops or nuclear weapons will be guided by his perception of what we—the United States or Britain—are likely to do in response.

Does my hon. Friend agree that the whole point of article 5 of the NATO treaty is not the question of which of the members of NATO an attacked country will look to to get most military help; rather, it is to take any uncertainty out of the question of who will declare war if a NATO country is attacked? Therefore, if a NATO country is attacked, our existing obligations are to declare war on the attacker. Does that not mean that we must be very careful how widely we extend NATO membership?

I agree absolutely, and that is a very important point. This NATO obligation is an unbelievably serious and important obligation. We have stretched it absolutely to its breaking point. If we are going to be serious about it, we have to follow through and that absolutely means we should not be giving guarantees to people we have no intention of protecting. We should not be writing cheques we are not prepared to have cashed.

The nub of this issue is, of course, that deterrence depends not on whether Britain would use a nuclear weapon, but on whether the other side believes that we would use it. Therefore, the most important support for our nuclear warheads lies not in the Trident missiles or even the submarines; it lies in the character of our nation, which is why there is absolutely no point in our having a discussion about a nuclear deterrent without looking at our defence strategy and posture in general. Deterrence cannot make sense if we get ourselves into a situation, which I sometimes worry my hon. Friend the Member for North Devon (Sir Nick Harvey) is getting himself into, where we believe that simply investing in fancy bits of kit is going to keep us safe. If people do not believe we are going to use them—that we are serious about using them—they will be entirely meaningless.

We can see the problems already, so let us just run through the various justifications that have been laid out here for nuclear weapons. The first was P5 membership. The big question for Britain on P5 membership is whether we are serious about our role in the United Nations at all. Why are we not contributing more to UN peacekeeping?

The subject of Iraq has been raised. The big question on Iraq is not our posturing about caring about terrorism or saying it is a tier 1 threat, but what we are actually doing? At present on the ground outside Kurdistan, while Australia has 300 soldiers, and Italy and Spain are deploying 300, we have exactly three. That means that Britain is not displaying and consistently demonstrating seriousness. This is not about combat troops; it is about being able to analyse the mission, have an intelligent conversation with the Iraqi Government, engage with our coalition allies and play the global role that our enormous defence budget is supposed to provide us with.

On Ukraine and Russia, again, we cannot simply rely on kit; we need to be doing things. The big question for us in Britain is how are we responding to the ambiguous warfare that we can see being propagated in Ukraine? What kind of investments are we making in military intelligence? What kind of investments are we making in cyber and in special forces? How much do we understand the situation on the ground in Ukraine and Russia?

On NATO, it is fine to talk about how important it is for us to be in NATO and to have nuclear weapons, and indeed it is. But it is meaningless if we are not going to stick to the commitments that we made in Wales of 2% of GDP. The most important thing we can do to deter Russia now is to ensure that Russia believes that NATO is serious about defending itself. If we say in a Wales summit that we will spend 2% of GDP, and if we go around telling other countries to spend 2% of GDP—and we should be telling other countries to spend 2% of GDP—we must retain our own promise and commitment, otherwise the nuclear deterrent will not be taken seriously.

Putin will look at us and ultimately conclude that there is a minimal chance of our doing anything if he were to intervene in the Baltic, because in respect of the rapid reaction force commitments, the framework nations—Germany, France and Britain—appear to be struggling to commit in 2016 to maintaining a deployable brigade. It seems to be very difficult to get the countries to work out how that will be funded in 2016. Whereas Russia can deploy 40,000 troops at 72 hours’ notice, the NATO deployment rates are running at about six months.

If we do not reach out to the public, which is why this debate is important, if we do not talk about why Britain is a global power, why we care about the Baltic, why we care about the global order, why we set up NATO, why we have nuclear weapons in the first place, all this will be lost.

To conclude, the fundamental rationale for all this depends on something on which the hon. Member for Newport West (Paul Flynn) and I disagree. This is the nub of the disagreement: do we believe in a world order? Do we believe in NATO? Do we believe Britain is a global power? Do we wish to play a role in the world? If we do, I will vote in favour of those weapons, but the deterrent will not make sense unless the character of the nation is in place, otherwise what we will be doing is creating something a little like the gold inkstand on the Table—a golden pinnacle on top of a cathedral, when the foundations and the structure of that cathedral are lacking and the faith of the nation has been lost.

It is a great pleasure to follow the hon. Member for Penrith and The Border (Rory Stewart). There was a time when we paddled together down the Thames in a canoe, I recall, but this afternoon we are certainly not paddling in the same direction at all.

I have been struck by the many themes of this debate. Two themes come to the fore—security and the avoidance of the real issue in its many forms. On security, it seems to be the view of the UK Government—perhaps this is an emerging view—that any Government not holding nuclear weapons are not taking defence and security seriously. That was the view of the Defence Secretary.

The logical upshot of this Pyongyang policy, which may now be the London Tory policy, is that everybody should have nuclear weapons. It is the global equivalent of the USA handgun policy, and we know what trouble that has created in the society of the United States of America and the deaths and destruction caused by widespread armaments, whether they be personal in one society or global across many countries that have weapons of mass destruction.

Under scrutiny, the Defence Secretary’s position melted. When I asked him about other Governments not having nukes, he dodged the question, unable to defend his logic. After being pressed further by the hon. Member for Brighton, Pavilion (Caroline Lucas), he still could not support his assertions. Despite the assertions and bluster that those who do not have nukes do not take defence and security seriously, the reality is to the contrary. As my hon. Friend the Member for Moray (Angus Robertson) pointed out earlier, the current NATO Secretary-General and his predecessor are from Norway and Denmark respectively. Are the UK Government saying that people such as Jens Stoltenberg and Anders Fogh Rasmussen do not take defence and security seriously? I think not.

The Secretary of State went on to say that political parties that do not approve of a deterrent are irresponsible. I challenge him, or members of his Government, to tell me whether it is now the view of the UK Government that any political party in Europe that is opposed to nuclear weapons is irresponsible. Is it the UK Government view that any political party on the globe that is opposed to nuclear weapons is irresponsible? That certainly seems to be what they are saying. My argument is to the contrary: they are being very responsible indeed.

The hon. Gentleman will be aware that there are powerful arguments on both sides of the Trident debate, particularly in Scotland, which generates certain strains. Nowhere is that more true than in the hon. Gentleman’s party, which recently voted on whether or not an independent Scotland would join NATO. Some members of his party who are genuinely opposed to nuclear weapons voted against joining, and so left the SNP; others voted for an independent Scotland to join NATO as long as the nuclear weapons were somewhere else—the nimby proposals. How did the hon. Gentleman vote on that issue?

Order. I am not singling out the hon. Member for Paisley and Renfrewshire North (Jim Sheridan), but interventions have been far too long, which is making speeches so long that soon we may have to set a time limit. That should not be necessary in a good debate such as this, in which interventions are to be encouraged because they make for a better debate. I simply make a plea for short interventions—I am not singling out the hon. Gentleman—so that everyone can contribute with long speeches and short interventions.

Thank you very much for that guidance, Madam Deputy Speaker. I am sure that it will be listened to by all Members present.

In answer to the hon. Gentleman, my hon. Friend the Member for Moray and I led the SNP debate on NATO. The policy seems to have been quite popular. Indeed, I am sure that the hon. Gentleman is well aware that the SNP is up in the mid-40s in the polls. Who knows? I may have played my part in securing that. I am sure that the hon. Gentleman is very pleased with the SNP’s current polling, which could have us winning as many as 50 seats at the general election. Who knows? It is certainly change for the SNP and, by definition, it is change for Labour in Scotland.

The hon. Gentleman says that it is SNP policy to join NATO. Does he therefore accept NATO’s nuclear umbrella? Would Ministers and armed forces personnel in an independent Scotland sit on the NATO planning group that controls its nuclear deterrent?

The hon. Gentleman will be aware that three of the 25 or 26 members of NATO have nuclear weapons. If we joined NATO, we would of course join other nations that have nuclear weapons, as well as nations that have maritime patrol aircraft, which the UK does not have. That would be an improvement. Scotland would certainly have maritime patrol aircraft.

I have given way enough; I want to make some progress. I have commitments, but if time allows, I will come back to the hon. Gentleman.

I was discussing the Government’s use of the term “irresponsible”. Why do they use such terms when they know that mainstream opinion is not behind them? It is because they want to create a phoney debate on a phoney choice. They want to give the public a very narrow view on what is actually a very broad mainstream consensus. The SNP, the Greens and Plaid Cymru are in the international mainstream of common sense, not blighted by the hangover of imperial lustre and the narrow thinking that controls too much of the UK debate on this subject.

This week on this issue and last week on austerity, we have seen two dividing lines in Westminster politics: austerity, supported by Labour and the Tories, and nuclear weapons, supported by Labour and the Tories—I am not quite sure where the Liberal Democrats are, but I am sure they will clarify their position. These are the new dividing lines in politics, and these are the choices that people face. This is a tectonic shift in politics.

There are people in the corridors of Westminster who are even talking about the prospect of a Labour-Tory coalition, and even if that is tongue in cheek, it throws up a huge challenge on nuclear weapons and austerity—a challenge squarely laid at the feet of the broadcasters. Do they have a debate based on a false pretence, with Labour and Tory agreeing on nuclear weapons and austerity, or do they do a real public service and show that there are real choices to be made? Any free society should show that and should freely challenge these assertions; otherwise, the impression will be given by the broadcasters that anybody opposed to nuclear weapons is not taking defence and security seriously, and these matters will not be challenged.

I challenge the hon. Gentleman again. He says that he wants to be part of NATO, which is SNP policy. Does he therefore agree that he will be joining a nuclear alliance, and that if we had an independent Scotland, members of that Government would sit on the NATO joint nuclear planning policy group? Is it not a fact that the SNP will, by joining NATO, be joining a nuclear alliance, so the hon. Gentleman cannot claim that an SNP Government will be completely non-nuclear?

It seems that the hon. Gentleman did not hear me the first time. By joining NATO, Scotland would be joining a club, 90% of whose members do not have nuclear weapons. Scotland would be one of those nations. The hon. Gentleman seems to be having some difficulty comprehending that—[Interruption.] No, he has had his answer, even if he cannot comprehend it. We will fulfil our obligations in NATO. The hon. Gentleman can ask again and again, and he will find the same difficulty in understanding it.

But the hon. Gentleman misses the point. Scotland would be a member of the nuclear planning group, even though it did not have nuclear weapons on its soil. If the SNP were to rule Scotland, would it be a member of the NPG or not? Everyone else is!

The hon. Gentleman tempts me on the rule of Scotland, but my final word on this is that we will fulfil our full NATO obligations as a non-nuclear member of NATO. About 90% of its members have no difficulty with that. My goodness, there is all this excitement about Norway and Denmark as well as Scotland—Members should get over all this!

I listened intently to the speech by the right hon. Member for Lewisham, Deptford (Dame Joan Ruddock). She mentioned the 1980s—a time I clearly remember as a teenager, when nuclear annihilation was seriously talked about and people did seem to comprehend the awful, frightening and terrifying possibility of the use of nuclear weapons. Over time, people have perhaps become more blasé and this has crept into our discourse, so there is a not as much understanding of the insanity of nuclear weapons as there used to be. That may be to protect our own sanity personally from day to day, because if we were to comprehend it, it would blight our lives. We have a feeling of powerlessness about it, so why worry about it day to day—if it is going to happen, it is going to happen. I say as a crofter from the highlands, however, that this is akin to the happy lambs who play in a meadow unaware of the autumn slaughter—the mass slaughter—to come.

The right hon. Member for Lewisham, Deptford reminded us of the wisdom and courage of Colonel Petrov, who had the data and information available to his senses from the best technology available at that time—that the west had fired five nuclear weapons at the USSR. What would have happened if he had acted in the way he was meant to act or in the way we were told he would act, or if he had acted logically on the basis of MAD—mutually assured destruction? If my memory serves me correctly, this comes from the theories of John Nash, the Nobel prize winner in economics. If Colonel Petrov had responded in that way, I would not have seen my 16th birthday. I have thus had 28 bonus years as a result.

If Colonel Petrov is still alive, I say that if ever there were a man deserving of the Nobel peace prize, it is certainly he. We were saved by our alleged enemies—perhaps by their humanity. We were saved again by a Soviet submarine commander during the Bay of Pigs incidents in Cuba in the early 1960s. The actions of those two men disproved the MAD theories, which were the foundation of the nuclear club to which the UK had itself belonged. They behaved in a way in a way that was outside MAD. They did not do mutually assured destruction, although they thought they would be destroyed themselves.

As the right hon. Member for Lewisham, Deptford said, our luck will eventually run out. Nuclear weapons have been in the hands of human beings for only 70 years. Given the two near misses that I have cited—and there have been more—I invite Members to engage in a thought experiment. Had nuclear weapons existed since Roman times, how much would history have progressed before nuclear annihilation? If we extend our 70 years to 140, or 210, or 300, how long will it be before it all goes wrong and our luck runs out? If our luck does run out, it will run out big style. I have to say, with respect to my friends in the Green party, that it is not gradual global warming that should be worrying us, but immediate global frying and the destruction of all creation—a sin like no other, which may result from omission or commission.

There will be more years of this possibility if mankind continues to possess nuclear weapons. The statistical chance of their use keeps increasing. If we had had them in Roman times, many events in history might not have happened. The world could have ended in 300 AD. If nuclear weapons had fallen into the hands of a Hitler, a Genghis Khan or even Jihadi John, or any similar despot or madman, he would have used them and the planet would have been destroyed. MAD—mutually assured destruction—could well have been framed for such people.

Nuclear weapons seem, bizarrely, to be subject to the law of triviality, which was summed up well by C. Northcote Parkinson in his 1959 book, “Parkinson’s Law, or the Pursuit of Progress”. If you will indulge me, Madam Deputy Speaker, I shall quote from it. Parkinson said:

“The Law of Triviality...briefly stated, it means that the time spent on any item of the agenda will be in inverse proportion to the sum involved.”

I would add “or to the danger of the position.” I believe that the £100 billion cost of the renewal of Trident will go through on an extremely small nod. Indeed, the issue is so trivial that Labour in Scotland has described tonight’s vote as meaningless, and its newly elected leader has described his party’s former policy of unilateral nuclear disarmament as a “flirtation with surrealism”. As was pointed out by the hon. Member for Barrow and Furness (John Woodcock), Labour has indeed moved, and that is why the polls are showing what they are showing in Scotland. It seems that Labour policy is not to engage properly in this debate, at a time when food banks are on the rise and Labour is supporting austerity.

Perhaps there is some movement in a graveyard in Cumnock where lie the remains of Keir Hardie, because it is a disgrace, and a significant example of the law of triviality, that Labour is ignoring this issue and is not taking it seriously. Parkinson’s law of triviality actually refers to something that deserves greater engagement and understanding.

I cannot believe what the hon. Gentleman has just said. At a time when submarines from Russia are going up the Clyde and tankers from the same place are at the top of Scotland, he is trying to tell us that we should not have a deterrent. That is absolutely unreal. The idea that we should find ourselves defenceless in those circumstances is a crazy notion.

This is not the first time that the hon. Gentleman has struggled to comprehend or believe things, but it is very alarming that he has told us that Russian submarines are going up the Clyde. My goodness! I thought that we had a deterrent. It is clear that his nuclear policies are failing, because by the sound of things, those submarines will be docking in Greenock or Port Glasgow any minute now.

This is not a trivial matter, and it is perhaps due to the difficulty of comprehending it that it is subject to the law of triviality. If ever there was an issue that required engagement for the safeguarding of our future and that of the planet, it is the awfulness, the ghastliness, the death and the destruction that nuclear weapons could cause—and perhaps, sadly, will cause one day.

I begin by saying a word in defence of the Labour party. Scottish National party Members seem to regard anyone who disagrees with them as trivialising the subject and anyone who agrees with them as taking it seriously. I personally greatly value the bipartisan approach taken by successive Labour and Conservative Governments to the maintenance of the nuclear deterrent. It is true that for a few years in the 1980s, the Labour party was captured by its left wing and went down the unilateralist road, but after two massive election defeats in 1983 and 1987, when the nuclear deterrent issue was central to the campaigns, the Labour party changed back to its bipartisan policy of nuclear deterrence.

We saw that reflected the last time we had a vote on this subject, as far as I can recall, which was on 14 March 2007. Tony Blair was still Prime Minister and he was proposing the approval of the renewal of the nuclear deterrent—the first stages of the process which should have got to maingate during this Parliament but are now due to get there in the next one. In that debate, we saw something interesting: almost all the Conservative MPs voted in favour of renewing the nuclear deterrent and keeping it in existence for the next generation; a considerable majority of Labour MPs were also in favour, but a sizeable minority of about 90 were opposed—they were the CND supporters who have been consistent in their principled opposition to nuclear weapons throughout their political lifetime; and also in the “against” camp were the Liberal Democrats and the nationalists. The result of that vote came about because of an agreement between the Front-Bench teams, with the motion being carried by 409 votes to 161.

That vote represented something more than a decision taken in this House; it also represented, quite fairly, the general spread of opinion consistently in this country throughout the cold war and in the years afterwards. When the fundamental question is asked in poll after poll, “Do you think that Britain should continue to have nuclear weapons as long as other countries have them?”, almost exactly two thirds of the population say yes and almost exactly one quarter say no, with single figures or thereabouts, if my arithmetic is correct, for the undecided. It is indeed a very divisive issue and it is one on which it is difficult to have a foot in both camps, although, as we have seen today, our friends the Liberal Democrats are doing their best to do that.

The hon. Gentleman will probably know that the last time this was debated was in 2007—and there was a vote—the majority of Scottish MPs voted against—we had an example of English votes for Scottish bombs.

I was generous in giving way to the hon. Gentleman so soon after he has made his own contribution. All I would say is that I know there was a vote on that day—that is what I just said—and if he tells me that a majority of Scottish MPs may have voted the other way, I accept that; but Scotland is, by choice, part of the United Kingdom and decisions on issues such as this are decisions for the United Kingdom as a whole. I do not believe even the SNP thinks that devo-max ought to include defence policy. If it does, we are in an even worse situation than I anticipated.

We heard from the hon. Member for North Devon (Sir Nick Harvey), who is a friend of mine, about moving away from the cold war. What one moves away from, one can move back to, and more quickly than one anticipates—particularly if, as the Chairman of the Defence Committee, my hon. Friend the Member for Penrith and The Border (Rory Stewart), said in his excellent speech, one’s enemies or potential enemies have good reason to doubt one’s will and determination to stand up for the agreements one has made and to use the deterrent power one has to prevent war from breaking out in the first place. I was very surprised that the hon. Member for North Devon did not think that the events in Ukraine had any bearing on our discussions today. I think the events in Ukraine are highly relevant, particularly as NATO has a rather strange open-door policy to membership, which it should not have. It should not grant membership to any country that we are not prepared to go to war for if it is invaded.

Does the hon. Gentleman also accept that the importance of Ukraine and Kiev is that this is the first time that we have had a unilateral breach of international borders since world war two? It is the kind of thing that we thought would not happen again, and it has, so the context remains the same.

It does indeed, and what really worries me is that because the intensity of the fighting has been so great, it is easy to imagine that it could spill over into a nearby country that is a member of NATO. If that happens, we would be at war with Russia. It is frightening to think what our summer would have been like if we had previously gone down the route of admitting Ukraine to NATO membership, sympathetic though we are. I remember that we stood by during the uprisings in central and eastern Europe that occurred when half the continent was under Russian control. We were very sympathetic to the Hungarians, and I remember with total clarity that we were terribly sympathetic to the Czechoslovakians, but nobody seriously suggested that we could go to war for those countries because of the geopolitical realities at that time.

I seem to recall in December 1994 that four nations—three nations and Ukraine—guaranteed the sovereign integrity of Ukraine in return for it getting rid of its nuclear weapons. It has got rid of its nuclear weapons, but we have not guaranteed its security.

Yes, and that should serve as a warning to us not to enter lightly into agreements that we have no intention of defending—I mean defending in the military sense.

It is just over 100 years since the outbreak of the first world war. I remember looking back in the archives of the inter-war period when a great debate was raging over whether or not it was safe to continue with the 10-year rule. I have mentioned it in the House before. It is highly relevant, so I will mention it again. The idea of the 10-year rule was that the Government would look ahead for a decade and see whether they thought there was any danger of a major war breaking out. If they did not see any such danger, they would cut the defence budget. That was rolled forward from 1919 right through to the early 1930s when it was eventually scrapped when Hitler came to power. It had a very damaging effect on our level of preparedness.

Lord Hankey, as he later became, was the Military Secretary of the Cabinet. In 1931, as an argument for scrapping the 10-year rule, he looked back to that summer of 1914 and said that far from having 10 years’ warning of the outbreak of the first world war, we had barely 10 days because of the rapidity with which the various alliances triggered each other into action. Suddenly, from nowhere, we have found ourselves drawn into a conflict with practically no notice whatever.

My hon. Friend pointed out in an essay that Maurice Hankey had said that we had failed to predict the 1870 Franco-Prussian war. Most recently, we failed to predict Russia going into Ukraine and Daesh taking over western Iraq, so I agree very wholeheartedly with my hon. Friend.

I am flattered to know that my hon. Friend the Chairman of the Committee reads my writings, and even quotes them back to me. I am very grateful to him.

I want to stress that I believe that the SNP has chosen this debate today—I congratulate the hon. Member for Moray (Angus Robertson), who I am pleased to see back in his place to hear my contribution, on securing it—with a particular political scenario in mind. SNP Members know that the majority of Labour Members and their supporters across the country agree with the concept of nuclear deterrence. They know that an overwhelming majority of Conservatives agree with nuclear deterrence. They are hoping to obtain something that they can use in the event of a future hung Parliament, in precisely the way that the Liberal Democrats were able to use their bargaining power to secure the postponement of the passing of the maingate decision from this Parliament to the next one. I think that was a terrible decision and it set a terrible precedent, but I am greatly reassured by the strength of the speech made by my right hon. Friend the Defence Secretary today.

When my hon. Friend the Minister winds up, I wish to hear that something will be done about the future of Trident and the holding of the maingate vote on time, as scheduled, in 2016 similar to what we have said about other areas of policy. We have seen authoritative statements in the press that no coalition will be entered into by the Conservatives unless it provides for an in/out referendum on the EU; similarly we have seen that no coalition will be entered into by the Conservatives unless it provides for passage of the draft Communications Data Bill. Those are two very important issues, but I submit that the future of the British minimum strategic nuclear deterrent is just as important as those two issues, if not more so. Until that vote is held, and held successfully, I shall continue to press those on my Front Bench for a commitment that we will never again allow the future of the strategic nuclear deterrent to be used in the way that it was in 2010 by a minority party in coalition negotiations.

I feel I must correct the historical record. In the summer of 2010, a value-for-money study on the successor programme concluded that savings could be made by slipping the time scale slightly. This was not something the Liberal Democrats demanded, although it was something we welcomed. It had the happy consequence of moving maingate into the next Parliament, but it was not something we sought, demanded or—

Order. The hon. Gentleman spoke for 31 minutes, and very long interventions will not help those Members who want to speak.

I shall also try to be more concise in the remainder of my speech, Mr Deputy Speaker.

All I can say to the hon. Member for North Devon, whom I greatly respect and admire, is that he ought to have a word with the then president of the Liberal Democrats, who proudly proclaimed on the Liberal Democrats’ official website that it was entirely as a result of the Liberal Democrats that we had not taken the decisive step of signing the maingate contract in this Parliament. I can only leave them to decide the issue between themselves.

Let me return to some of the purely military arguments in favour of the continuation of the strategic deterrent, mercifully leaving the politics to one side. The most important argument, as I have stated in previous debates in this House, is the recognition that future military threats and conflicts will be no more predictable than those that engulfed us throughout the 20th century. That is the overriding justification for preserving armed forces in peace time as a national insurance policy. No one knows which enemies might confront us during the next 50 years, for that is the period we are discussing by the time everything is designed, constructed and deployed, and has served out its operational lifetime. It is highly probable that at least some of those potential enemies will be armed with weapons of mass destruction.

Secondly, it is not the weapons themselves that we have to fear but the nature of the regimes that possess them. While democracies are usually reluctant to use nuclear weapons against non-nuclear dictatorships, although they did so against Japan in 1945 as has been pointed out, the reverse is not true.

There is consensus in the international community about the Iranian nuclear programme and efforts to reduce it. Significant nuclear proliferation in the middle east is likely in the next 20 or 30 years, which feeds into my hon. Friend’s argument about the 50-year time span that we should consider in this debate.

It does indeed. I cannot think of an existing nuclear power that has done more than the United Kingdom to slim down and reduce the firepower of its independent nuclear deterrent. The response, as has been repeatedly pointed out by Government Members and by some Opposition Members, to those unilateral reductions on our part has been absolutely zero. There is not the slightest shred of evidence that if we were to abandon our nuclear deterrent completely any other country would follow suit. All that would happen would be that those near-misses, which have been discussed so eloquently today—the risks of nuclear Armageddon by accident—would continue between the superpowers if they are tangible risks, but we would add another risk: the risk that someone hostile to us with a nuclear armament could blackmail us into concessions, surrender or absolute annihilation. The risk of the deliberate firing of nuclear weapons against us is something that we would be crazy to accept voluntarily and unnecessarily.

Returning to the reluctance of democracies to launch nuclear weapons against countries that do not have them—although we use them, as I have said, continuously as deterrents—we should consider the alternative. If a dictatorship such as that in Argentina had had an arsenal of even a few small atomic weapons and the means to deliver them, no matter how many conventional forces we had had, we would not have dared to retake the Falkland Islands, because we must not project on to other countries that do not share our political principles and freedoms the sense of self-restraint that we apply to ourselves.

The third argument that I always outline is that the United Kingdom has traditionally played a more important and decisive role in preserving freedom than other medium-sized democracies have been able or willing to do. Democratic countries that do not have a nuclear deterrent have little choice but to declare themselves neutral and hope for the best or to rely on the nuclear umbrella of more powerful allies. The United Kingdom, for historical reasons, is a nuclear power, and it is much harder to defeat it than many other democracies by conventional means because of our physical separation from the continent.

The next argument is that our prominence as the principal ally of the United States, our strategic geographical position, to which I have just referred, and the fact that we are the junior partner might tempt an aggressor to risk attacking us separately. Given the difficulties of overrunning the UK with conventional forces, compared with our more vulnerable allies, an aggressor might be tempted to use one or more mass-destruction weapons against us on the assumption that the United States would not respond on our behalf. Even if that assumption were false, the attacker would find out his mistake only when it was too late for all concerned. An independently controlled British nuclear deterrent massively reduces the prospect of such a fatal miscalculation.

The fifth military argument, which was mentioned earlier, is that no amount of conventional force can compensate for the military disadvantage that faces a non-nuclear country in a conflict against a nuclear-armed enemy. The atomic bombing of Japan is especially instructive not only because the emperor was forced to surrender but because of what might have happened in the reverse scenario. If Japan had developed atomic bombs in the summer of 1945 and the allies had not, a conventional allied invasion to end the war would have been out of the question.

I tend to find that people wish to try to sweep aside the patent logic of nuclear deterrence by projecting on to historical figures events that did not happen and could never possibly be tested. The hon. Member for Na h-Eileanan an Iar (Mr MacNeil), who has now left his place, asserted that Hitler would not have been constrained by a nuclear deterrent held by the allies if he had had nuclear weapons. In 1943, Hitler proposed to use the nerve gas, tabun, which was far, far more deadly than the gases that the allies then possessed. When he consulted his chief scientists, they said that it was most unlikely that the allies had not discovered tabun too, and he therefore decided not to employ it, even though it would have had a devastating effect. That is an example of even Hitler being deterred by the mistaken belief that his enemies had a weapon when in fact they did not.

The hon. Member for Moray made his points with clarity and calmness, as always. He said that he did not think that deterrence had worked. Of course, when something does not happen—that is, world war three—it is difficult to show that it would have happened if one had done something different. However, I always apply the test of the proxy war. The right hon. Member for Lewisham, Deptford (Dame Joan Ruddock) observed that throughout the cold war period many proxy wars went on around the globe. In fact, that is an argument in favour of the case that nuclear deterrence had something to do with the fact that the superpowers did not fight each other in Europe. If no other conflicts had been going on among proxies of the superpowers, one could have argued that they would not be likely to have been at each others’ throats if they did not have a nuclear deterrent. The fact that they were fighting each other by every means possible other than open war—state to state—on the European continent strongly suggests that the possession of the nuclear deterrent, and the balance of terror, had something to do with that stability.

The hon. Gentleman will no doubt agree that in the preceding period, which is the only thing we can base our evidence on, there was a whole series of European wars with the major powers fighting each other.

Exactly. That leads us back to the heart of what the concept of deterrence requires in order to work. Deterrence means that a potential aggressor must not only face a degree of retaliation that is unacceptable if inflicted, but be convinced that that retaliation is unavoidable.

The key point about nuclear deterrence was made in a 1945 study by the leading defence scientist when nuclear weapons were first being considered as a concept. I love quoting the example—I have done so on previous occasions—given by Professor Sir Henry Tizard, who was one of the chief scientific advisers to the wartime Government, when he first considered what the atomic bomb would mean if it worked. He said that he could see no way of preventing an atomic bomb from being used except by the fear of retaliation, and he illustrated that by saying:

“A knowledge that we were prepared, in the last resort”—

our deterrent has always been the final resort, if the future existence of the nation is at stake—

“might well deter an aggressive nation. Duelling was a recognised method of settling quarrels between men of high social standing so long as the duellists stood twenty paces apart and fired at each other with pistols of a primitive type. If the rule had been that they should stand a yard apart with pistols at each other’s hearts, we doubt whether it would long have remained a recognised method of settling affairs of honour.”

The hon. Member for Moray referred to a number of things that I will touch on briefly. He talked about our obligations under article VI of the non-proliferation treaty, which states:

“Each of the Parties to the Treaty undertakes to pursue negotiations in good faith on effective measures relating to cessation of the nuclear arms race at an early date and to nuclear disarmament, and on a treaty on general and complete disarmament under strict and effective international control.”

The only thing that is time-limited in that commitment is the cessation of the nuclear arms race at an early date. We are not engaged in a nuclear arms race with anyone. We never have been and we have successively, as I said earlier, been reducing our capacity with little or no response from the other nuclear powers.

The other two, open-ended commitments are to achieve nuclear disarmament and to achieve general and complete disarmament. The article wisely recognises the link between the two, because one thing we do not wish to do by removing the balance of terror and by achieving even multilateral nuclear disarmament is to make the world safe again for conventional conflict between the major powers.

Will the hon. Gentleman update the House on the initiatives led by his Government to fulfil their obligations? He will forgive me, but I have not caught up with the discussions his Government have had with other nuclear powers to fulfil those obligations.

I do not think the hon. Gentleman has understood the three obligations I have listed. The first is to work for the cessation of the nuclear arms race—we are not a part of the nuclear arms race—at an early date. The second is to achieve world nuclear disarmament, and the third is to achieve general and complete conventional disarmament. I believe that those are, frankly, utopian visions that we work towards but which suffer setbacks according to the state of the world at any time, and the state of the world at the moment is one of grave disturbance and serious potential threats.

I am sorry that I missed the earlier part of my hon. Friend’s speech. Surely the point is that there is no obligation at all to disarm unilaterally in any shape or form, yet that seems to be the policy favoured by the supporters of this motion.

I entirely agree.

I must bring my remarks to a close for the sake of other Members, but I would simply say that, although much has been said about the cost of the deterrent, so far as I know our deterrent has never amounted to more than 10% of the overall defence budget. Arguments about the deterrent must be made on the basis either that people believe it is necessary to have one to prevent this country from facing nuclear blackmail, or they do not. If people believe that a deterrent is necessary for such a role, 10%, 20% or even 30% of the defence budget is not too much to pay. Fortunately, we will not have to pay anything like that sum. It is comparable with the cost of the High Speed 2 rail system that we propose to build. In my opinion, our priorities should lie in a slightly different direction, given the cuts that defence has taken.

My hon. Friend is an expert on these matters and is making a compelling case. Does he agree that it would be completely naive to accept the SNP’s position as set out in the motion, particularly in thinking that if we disarm in this sense, others will follow?

Yes, indeed. As I said, the evidence points in the opposite direction.

I have covered the point about gaps in conventional capability. If the nuclear deterrent were scrapped, there is no guarantee that the money saved—all of it, or even any of it—would be put towards conventional forces. Even if it were, no amount of conventional forces can compensate for the absence of the ability to deter nuclear blackmail.

We have heard in graphic terms the consequences of the explosion of a nuclear weapon. All I can say is that everybody agrees it would be a disaster if nuclear weapons were fired and exploded. The question is: what is the best way of preventing that from happening? Time after time, when asked the key question about keeping a nuclear deterrent as long as other countries have one, people have shown in overwhelming numbers that they subscribe to the route of peace through deterrence. I subscribe to that, as do most Labour Members, but the smaller parties do not. It would be an outrageous betrayal of the first duty of government—namely, defence—if either of the two main parties, if there were a hung Parliament after the next election, allowed this matter to become a negotiating issue in forming a coalition. The issues at stake are far too