Policy Papers

Upgrading Britain’s nuclear deterrent: from V-Bombers to Trident replacement

Matthew Grant |

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Executive Summary

  • The debate taking place over the replacement of the Trident nuclear submarines involves the same complex interplay of elements which characterised previous discussions about upgrading Britain's nuclear deterrent.
  • These elements are strategic, technological, diplomatic and political in nature, and stretch back to the replacement of the V-Bombers in the late 1950s and early 1960s.
  • Strategic arguments have continually stressed the 'unknowable' threats Britain might face in the future, and the need for an independent deterrent in case alliances collapse.
  • Technological advances forced the abandonment of any specifically 'British' weapons system during the Cold War and have continued to severely constrain the options available.
  • Diplomatic concerns have stressed the 'value' provided by the deterrent in bolstering British influence.
  • The domestic political context can play a pivotal role in shaping nuclear decision-making and it is not inconceivable that the current economic constraints could de-rail current government proposals.
  • Overall, the fear of risks to prestige and of military and strategic uncertainty over the long-term future have triumphed over concrete criticisms, resulting in repeated upgrades by the governments of the day: triumph of the much-derided 'precautionary principle'
  • A recent report from the Institute for Public Policy Research (IPPR), however, has criticised Britain's reliance on a United States-derived nuclear deterrent, stressing the need to explore alternatives such as the European dimension and emphasising the non-nuclear threats to Britain's security- the emergence of the recognition of competing precautionary principles.


The debate about upgrading Britain's nuclear deterrent has intensified over the last few years. In December 2006, the Labour Government announced in a White Paper, The Future of the United Kingdom's Nuclear Deterrent, that they would replace the submarines that carry Britain's deterrent (the 'Vanguard' class) when they begin to leave service in the early 2020s. The actual weapon, it was stressed, would remain the same, with the government extending the life of the Trident D5 missile which carries the thermonuclear warheads. The White Paper also signalled the government's commitment to nuclear disarmament by announcing a 20% reduction in warhead numbers, leaving a stockpile of 160 to provide a 'minimum' level of deterrence. When the policy document was debated in the House of Commons in March 2007, the Government's policy was approved by 409 votes to 161, receiving a large dose of Conservative support but also witnessing 88 Labour members refusing to back the plans.

Despite this vote, there is still no requirement for the government to upgrade its deterrent: it will be some time before the expenditure needs to be committed to procure contracts, but that time is coming closer. In September 2009, the Brown Government intends to announce its decision on the scale and nature of the new weapons carrier. However, the public debate surrounding the issue , has changed markedly in line with the radically different economic circumstances compared to early 2007. In the current recession, the bill for nuclear weapons is under more scrutiny, as are the strategic benefits they are meant to bring. Commentators from across the political spectrum have called for the Trident replacement plan to be scrapped, or at least postponed, with the money saved being spent on the NHS or on conventional forces depending on the commentator. 'Less bombs more hospitals' remains an evocative cry , and there is also logic in questioning the cost of the programme whilst Britain's over-stretched military seems starved of basic resources. An Institute of Public Policy Research (IPPR) Commission co-chaired by Lords Ashdown (ex-leader of the Liberal Democrats) and Robertson (ex-Defence Secretary and Secretary-General of NATO) reported in June 2009 that ways of delaying the replacement of Trident should be explored. The money saved could then be used to provide more flexible response to security threats.

The current debate about upgrading the deterrent echoes those over the decision to buy Trident in the early 1980s and its predecessor, Polaris, in the early 1960s. Many assume Brown will follow the lead of Margaret Thatcher and Harold Macmillan and press ahead, despite the concerns of a segment of public opinion - one opinion poll in 2007 suggested three quarters of the public supported either scrapping the programme or delaying any upgrade. There are many reasons that can and have been used for and against upgrading the deterrent, and just as importantly many reasons why a particular option has been chosen over another. These include decisions on strategy, technology, diplomacy and domestic politics; and a review of how past decisions have been made sheds light on the difficulties and uncertainties facing policy-makers today.


The basic question which must always be answered of Britain's nuclear deterrent is why is it needed? This did not unduly trouble the Attlee Government, who approved the construction of Britain's first atomic weapon, nor indeed the Conservative Cabinet of Winston Churchill, who were much more exercised about the manner in which the decision was taken than its substance. These decisions on arming Britain with nuclear weapons were based on two complementary factors: the inherent danger of the Cold War, and the potential unreliability of the United States as an ally. Perhaps surprisingly, more was made of the American dimension in the early Cold War years.; almost certainly because the threat of Moscow-directed communism to British national interests was already taken for granted. There was ministerial reluctance to rely totally on the American nuclear umbrella: memories of fighting Hitler alone in 1939-41, were still fresh. Attlee later recalled that the atomic weapon was necessary as 'we couldn't allow ourselves wholly to be in their hands, and their position wasn't awfully clear always'. Later, Churchill concluded that 'influence depended on possession of force', and Britain might need the leverage to dissuade the United States from a preventive war against the Soviet Union. All told, most British governments have agreed with Churchill that 'we must avoid any action which would weaken our power to influence United States policy'.

Later decisions were more troubling. Radical changes in technology meant that it was the delivery system, not the warhead, which was the most complex and expensive part of the deterrent. From the late-1950s until the purchase of Trident in 1980, British policymakers faced a series of decisions about the upgrading of the deterrent, forced upon them by the perceived need to protect it from becoming strategically obsolete. It was during these debates that conflicting arguments were made more strongly: the enormous cost involved, the reliance on the technology of other nations, the rise of disarmament opinion, and the decline in global prestige implied by possessing a deterrent that was not fully independent. Thus, the moment when the need for upgrade became apparent also became the moment when the need for its existence was questioned. At these moments, the strategic case for maintaining the deterrent needed to be stronger than ever.

When the Wilson Government came to power in 1964 the political arguments against maintaining the deterrent were at their strongest, at least for a governing party. Denis Healey, a committed advocate of the nuclear role, later justified the continuation of the Polaris programme in terms of the strategic 'uncertainties' of 1964: 'the Cuban missile crisis was only a year or two behind us, the memory of Hungary was still fresh in our minds, Khrushchev had been deposed the day before the British poll, the Chinese had just exploded their bomb on the same day - we felt, on the whole, it was wise to continue with it'. It was these uncertainties - of what had just happened, what was happening, and what could happen - which in the end justified maintaining the deterrent during the Cold War. Critics of current government policy argue that the lack of a nuclear-armed national enemy comparable to the Soviet Union makes a strategic deterrent redundant; threats to Britain's security cannot be 'deterred' in the way Soviet communist aggression was - how would a new generation of nuclear submarines stop terrorism, whether non-nuclear or nuclear, even? These are valid points, but the real strategic reason underpinning the decision to replace the Vanguard class submarines does not lie in current threats at all. The new submarines will carry the deterrent from the 2020s until the 2050s - and nobody, the argument runs, can know the threats Britain will face in forty-five years time.


The current debate over upgrading the deterrent breaks with the past in one area: unlike all other upgrades, it is not envisaged that the new system will entail a substantial advance in weapons technology. Instead, it is the submarines themselves, not the missiles, which need replacing. The active life of these missiles will be 'extended', probably by refurbishing the old ones, in conjunction the United Sates. Usually it has been the need for a technologically superior weapons delivery system which has driven the upgrading of the deterrent. When the atomic and thermonuclear decisions were taken in 1946-7 and 1954-55, Britain's deterrent was envisaged as being delivered by bombers. These aeroplanes, the jet-powered 'V-Bombers' were top of the range in the mid-1950s, but changes in anti-aircraft weaponry made them obsolete by the early 1960s. This signalled the start of a lengthy crisis over the credibility of the deterrent. A further problem, which typifies all discussions of deterrent upgrade, is the relationship between the long lead times for weapons development and the uncertain nature of future security needs.

This meant that technological developments could overtake new weapons, as happened with Britain's attempt to build a rocket-delivered deterrent capability in the late 1950s. This weapon, 'Blue Streak', was found to be vulnerable to Soviet strikes as it could not be fuelled and launched quickly enough if Britain came under attack. Its cancellation in 1960 instigated a major political crisis over the viability of the British deterrent. In the place of Blue Streak, and based on the awareness that the V-Bombers were increasingly unlikely to penetrate Soviet air defences, the Government agreed to purchase 'Skybolt' missiles from the United States. These 'stand-off' weapons would be launched from the V-Bombers and allow the aeroplanes to strike at a safer distance from their target. In December 1962, however, Skybolt was unilaterally cancelled by the United States (it was later described by US Defense Secretary Robert McNamara as 'a pile of junk'). This led to a hasty series of meetings from which emerged the Polaris Sales Agreement of 1963, which not only led to Britain buying the technology for the Polaris submarine-launched weapon system, but also formed the basis for the purchase of Trident, ensuring Britain's participation in the Trident D5 'life extension programme' and Britain's access to any successor missile.

The Blue Streak debacle meant Britain had to abandon its pretensions to compete with the superpowers in the development of missiles. The eventual adoption of Polaris, followed by Trident, and the possible replacement of the Trident D5 missiles in the future, mean that Britain's deterrent has been reliant on American technology since the 1960s. Both Polaris and Trident were advanced pieces of military kit beyond Britain's own technological reach. Polaris solved the problem of the first-strike 'bolt-from-the-blue' with its submerged missiles ever-ready to strike no matter how damaged the home nation. Trident's missiles were multi-warhead weapons capable of saturating any known defences. Britain's last attempt at a home grown system was 'Chevaline', an upgrade to Polaris deemed essential to allow the missiles to penetrate Soviet defences (by deploying decoys in the warhead). Chevaline was pursued for several reasons: the upgrade was deemed necessary; it was believed Britain could produce it; and the Labour Governments of Harold Wilson in the 1960s and 1970s had ruled out adopting a new generation of nuclear weapons. Whereas the United States had upgraded with the entirely new 'Poseidon', fear of disarmament opinion within Labour ranks played a large part in ensuring the 'Chevaline' route of 'improved' not 'new' weapons was followed. Spiralling costs and delays to Chevaline, which was planned in the mid-1960s but not fully deployed until 1982, convinced officials and politicians of Britain's inability to develop its own new weapons systems. When Polaris needed replacing, the Thatcher Government had fewer scruples than any of its 1970s predecessors about buying a new generation of weapons from the United States, and if an upgrade to Trident is purchased, then again, Britain will not be the prime site of its development. Due to the sheer complexity and cost of weapons development, Britain's choice has always been severely limited.


Strategic considerations are not the only reason why successive British governments have deemed nuclear weapons desirable, nor are technological factors the sole reason why a particular path has been chosen for new systems. Diplomatic factors have been vital in both instances and the level of international prestige and influence apparently provided by Britain's deterrent has always been a major reason for retaining it. As we have seen, the Anglo-American partnership has determined which nuclear system has been chosen, and in the 1950s and 1960s a great deal of diplomatic effort was expended in securing and then maintaining Anglo-American nuclear co-operation.

What are the diplomatic benefits for Britain? It has been widely assumed that the deterrent helps preserve Britain a permanent place on the United Nations Security Council. It also ensures Britain's position in discussions of disarmament and non-proliferation. In 1957 Aneurin Bevan famously castigated the supporters of unilateral disarmament for wanting to send him (as Shadow Foreign Secretary) 'naked into the conference chamber' - only if Britain possessed weapons could he help bring about multilateral disarmament. This is a justification today, and helps explain the Labour Government's decision to reduce the weapons stockpile as well as build a new submarine fleet - a policy of both deterrence and disarmament. Although the diplomatic impact of retaining the deterrent is impossible to gauge, the assumption that these weapons bolster Britain's prestige and her standing in the world has played an important role in ensuring they remain. As Churchill put it, 'it's the price we pay for sitting at the top table'. Overall, the importance of highly general notions of international prestige in determining Britain's nuclear future cannot be overstated.

Is the United States the only potential nuclear partner? The most recent historical research stresses that during the 1960s and early 1970s, there was the intriguing prospect of an Anglo-French nuclear partnership. The discussions came to nothing, but do emphasise that European alliances could give Britain another option when it comes to renewing the deterrent. Britain's reliance on American nuclear technology has caused problems before, such as when the Polaris Agreement emboldened Charles De Gaulle to reject the Macmillan Government's application to join the EEC in 1963. Moreover, Britain is effectively forced to bank on American goodwill in the purchase both of Trident and the participation in the D5 missile refurbishment programme. In 1973, however, Britain was warned against attempting to buy Poseidon from the United States as President Nixon's domestic troubles made it doubtful that Congress would approve of the sale. Problems in American politics effectively forced the Heath Government to give final approval to the Chevaline programme and demonstrated the flaws in relying so completely on the American connection. Any future successor to the Trident D5 missile will need to be compatible with the new British submarines, but will be designed in the United States. In the 1960s ministers feared that Polaris was overly-reliant on American technical support, which might be phased out as the United States replaced its system before Britain did, and this concern will continue to worry the government. Certainly the recent IPPR report criticises reliance on the United States as 'complacent' and calls for greater European co-operation. As yet, however, there has been little suggestion of a 'European' alternative to the new Trident submarines.

Domestic politics

The biggest criticism of the Brown Government's current plans focus on the cost implications. In the middle of a sharp recession, the multi-billion pound investment required seems an outrageous expense. The 2006 White Paper included a figure of £15 billion, but newspapers have been reporting figures of £40-£70 billion since March 2009 and the Ministry of Defence's poor record of procuring equipment on time and on budget adds further uncertainty. Either way, it is a considerable sum and given the timescale envisaged, may increase even more. As spending cuts bite in the coming years, pressure on the decision to buy the post-Trident submarines will probably mount both outside and inside the government. In 1946, the key economic ministers of the Attlee Government, Hugh Dalton and Sir Stafford Cripps, attempted to prevent the atomic bomb programme going ahead on economic grounds. In 1967 it was again economic Ministers who were most hesitant about committing to upgrade the Polaris weapon. In both cases, however, the strategic considerations won out.

Outside the confines of the Cabinet, backbenchers and political opponents of the current government have seized on the cost of the programme, and calculate the equivalent number of hospitals or army helicopters that could be provided instead. Outright disarmament sentiment of the Campaign for Nuclear Disarmament variety currently has little mainstream political purchase, but in the early 1960s it garnered a wide degree of sympathy from Labour politicians. It severely restricted the Wilson Government's ability to manoeuvre and led to a rather dishonest justification for continuing Polaris in 1964 on the grounds that it was too far advanced to cancel; it was also a major factor in ensuring the government did not purchase Poseidon in 1965-68, which would have been politically impossible. Moreover, the Labour Party's commitment not to advance to a new generation of nuclear weapons probably helped deter the Heath Government from risking an approach to the Nixon Administration to buy Poseidon in the early 1970s, as a future Labour Government might cancel it. Thus, although the wishes of those outside the Cabinet may seem rarely to have influenced nuclear decision-making, the domestic political context can play a pivotal role in deciding the final outcome, often in surprising ways. The domestic political context is all the more important today. The parliamentary vote on the 2006 White Paper was a rare occasion when dissent could be registered before the deal was completed; pressure in the House of Commons really could derail the whole programme, especially as opposition to an early decision is mounting not just amongst 'disarmament' opinion, but from within the pro-nuclear 'traditional' establishment.


In the 2006 White Paper, Tony Blair argued that 'those who question this decision need to explain why disarmament by the UK would help our security.... They would need to argue that the UK would be safer by giving up the deterrent and that our capacity to act would not be constrained by nuclear blackmail by others'. This is an inversion of the usual argument, which seeks positive reasons for Britain's nuclear deterrent. Blair, however, suggested that reasons were needed to disrupt the status quo rather than to maintain it. This stance illustrates that - if not quite the law - possession in nuclear matters is nine-tenths of the argument. Essentially conservative in nature, this argument is entrenched by the knowledge, expressed recently by David Young (a Ministry of Defence insider during the key discussions about Chevaline in the early 1970s) that 'once you give this up you are done, you will never go back and you can never afford to start again . . . and in the end, over and above the financial and military arguments, there is a powerful political argument'. So for all the considerations of cost, and notwithstanding the diplomatic, political, and technological ramifications of the decision, it is perhaps fear that has ensured Britain still has a nuclear deterrent, and probably still will in the 2050s; fear of taking an irrevocable step, fear of the future, unknown strategic landscape, fear of Britain's diminished place in the world and fear that history will judge those who dispensed with the deterrent as having left Britain unarmed. In this sense, the series of decisions that have ensured Britain is a nuclear-armed power today can only partly be understood as being based on a rational understanding of strategy and diplomacy. We must also take into account the less rational aspects, the assumptions, the deep-seated cultural belief within British governments, Labour and Conservative, that nuclear weapons are essential. This has been one area of political decision-making where the much-derided 'precautionary principle' seems to have consistently ruled the roost.

In contrast, the recent IPPR report recognises the possibility of alternative and competing precautionary principles that should be placed in consideration, notably whether a commitment to the replacement of Trident carries an opportunity cost of tying Britain too closely to a single ally and its associated global strategic interests, the outsize superpower of USA, possibly at the expense both of preserving more independence and flexibility geo-politically and of closer co-operation with our principal trading partners and geo-political neighbours in Europe. Despite these alternatives, however, the Government's recent decision to exclude the discussion of Trident replacement from its forthcoming strategic defence review - elevating it, in the words of one insider, to 'sacred cow' status - suggests that the factors which have determined nuclear policy over the past forty years still hold sway in today's Whitehall.

Further Reading

John Bayliss, Ambiguity and Deterrence (OUP, 1995).

Matthew Grant (ed), The British Way in Cold Warfare: Intelligence, Diplomacy and the Bomb (Continuum, 2009).

Catherine Haddon, 'Cabinets and the Bomb', British Academy Review, 10 (2007), pp.28-30 (see an edited transcript of the 'Cabinets and the Bomb' Workshop, held at the British Academy in March 2007)

Peter Hennessy, The Secret State: Whitehall and the Cold War (Penguin, 2003)

Peter Hennessy, Cabinets and the Bomb, (OUP, 2007).

Institute of Public Policy Research Commission on National Security in the 21st Century, Shared Responsibilities (Institute of Public Policy, 2009)

Ministry of Defence, The Future of the United Kingdom's Nuclear Deterrent, Cm. 6994 (The Stationery Office, 2007).


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