Why is the UK reversing progress on disarmament?

The UK’s decision to increase its nuclear warhead stockpile is the most significant change to the country’s nuclear posture since the end of the cold war. In place of a 2010 pledge to reduce the stockpile cap from 225 to 180 by the mid 2020s the stockpile cap will now be raised to 260. The change is such a radical departure that early leaks to the press were met with scepticism from analysts and suggestions that any announced change would simply involve a delay to the reductions. So why is the UK reversing progress on disarmament?

The change was announced in the government’s long-awaited Integrated Review (IR). A successor to the 2010 and 2015 Strategic Defence and Security Reviews (SDSR), the Integrated Review was intended to avoid the mismatch between budget and ambition that dogged those two documents. It also had a broader scope, encompassing the work of the Foreign Office and the now abolished Department for International Development, as well as military strategy. Announced shortly after the 2019 election, the IR was originally due to conclude in autumn 2020, but was delayed due to the coronavirus pandemic. The government announced £16.5bn of additional military spending last November, but the IR itself was released on March 16th.

Previous stockpile figures

The 1998 Strategic Defence Review announced a one-third reduction in the UK’s warhead stockpile. This followed the removal of the air-launched WE-177 nuclear weapon from service, which brought the stockpile down from around 400 at the end of the 1980s to around 300. At the time of the 2006 vote to replace the Trident submarine fleet the government announced a reduction in the number of ‘operationally available warheads’ to 160 and a 20% reduction in the overall stockpile.

The 2010 SDSR published official figures for both the overall stockpile and the number of operationally available warheads and announced planned reductions to both. The stockpile cap would be reduced from 225 to 180, and operationally available warheads would be reduced from 160 to 120. Figures were also given for the number of missiles and the maximum number of warheads that would be carried on each submarine. These were reduced to 8 and 40 respectively. These figures and the planned reductions were confirmed in the 2015 SDSR. At its peak in the Cold War the UK warhead stockpile was estimated at 520.

The Integrated Review

The IR justified the increase in the stockpile cap in terms of the “the evolving security environment, including the developing range of technological and doctrinal threats”. As well as reversing the trend in reducing warhead numbers, the IR also reversed the previous policy of transparency about the operational stockpile and the numbers of warheads per missile and submarine, meaning that the only information now given is the stockpile cap. This was also said to be due to the “changing security and technological environment”.

The long-standing declaratory policy that the UK wouldn’t use nuclear weapons against a non-nuclear member of the Nuclear Non-Proliferation Treaty (NPT) in compliance with the treaty is re-stated in the IR, but has been further qualified. The government now says it could review the policy if facing a threat from “weapons of mass destruction, such as chemical and biological capabilities, or emerging technologies that could have a comparable impact.”

It has also been suggested that the UK may intend to deploy more than one nuclear-armed submarine at sea. The 1998 SDSR set the current policy of only one submarine patrolling at a time. However, the previous figure for operationally available warheads was equivalent to a full load of warheads for the three submarines that are not in deep maintenance at any one time, so there is no obvious reason that deploying more than one submarine at sea would require an increase in the overall stockpile. It is more likely that the stockpile increase will involve an increase the number of warheads per submarine, but no conclusions can be drawn about a change in plans for submarine deployment.

An increased stockpile certainly gives more leeway for slower maintenance and redevelopment of warheads stockpile, as more could potentially be out of service at any given time. If this is a consideration, the well-documented delays to AWE Burghfield’s MENSA project may be a factor in the decision. Had this facility been built on time it would likely have been used to decommission the warheads in order to make the reductions planned in 2010. Even if the reduction plans had been retained it is likely that a delay would have to have been announced as warhead convoy movements have not been consistent with any substantial stockpile reductions.

Contradictory justifications

The introductory paragraph to the nuclear weapons section in the IR links to the basis of new offensive capabilities being developed by other unnamed nuclear armed states. This is presumed to be a reference to Russian and Chinese developments. However, this justification undermines the long-standing government rationale for the UK’s nuclear weapons. The claim is that they deter aggressive action from other states by threatening “unacceptable damage” in response: the so-called ‘Moscow criterion‘. The size of the UK’s nuclear arsenal was calculated according to a requirement to destroy a network of command bunkers around Moscow, and the development of offensive capabilities by other states would not prevent a UK nuclear strike from achieving that goal.

After the IR was released there was a suggestion by the Defence Secretary (pictured above) that the actual reason for the stockpile increase is an increased Russian defensive capability. This justification is more coherent in terms of the deterrence rationale for the UK’s nuclear weapons. But the text in the IR only discusses offensive capabilities and ‘threats’. This mixed messaging from the government undermines the justifications given in the IR and lends weight to the charge that the change is more a consequence of “toxic domestic posturing” than being motivated by external events.

While the change will have been justified internally with policy papers along the lines of the rationales that have been hinted at in public, decisions at the political level may have been taken on less sophisticated grounds. Sources from the Ministry of Defence quoted by the Guardian’s Defence Editor said the policy was motivated by a desire to be “more assertive” and “not apologise for” the UK’s nuclear weapons. The fact that numerous sources leaked the policy and were critical of it suggests that there was significant contestation within government and that the internal justifications were not universally convincing.

Diplomatic consequences

Under the nuclear non-proliferation treaty (NPT) the UK is obliged to pursue disarmament in good faith. Amongst the 13 steps agreed to by the UK and the other four NPT nuclear weapon states at the 2000 NPT Review Conference are commitments to diminish the role of nuclear weapons in security policy and apply the principle of irreversibility to disarmament measures. As the UK has previously said that the planned warhead reductions were part of a “step-by-step approach to nuclear disarmament”, it would appear to be in breach of both of those commitments.

The Review Conference that marks the NPT’s 50th anniversary has been postponed due to the coronavirus pandemic, but is due to be held in August. Following the failure of states parties to agree a consensus document in 2015, there is a considerable pressure on states to reach consensus at the forthcoming conference. However, the scale of frustration with the lack of progress on disarmament makes a consensus document unlikely, and the UK’s decision will only further inflame the situation. The criticism already voiced by the UN Secretary General and the German foreign minister about the decision will likely be echoed by many states at the conference in August, and the UK could find itself held responsible for a further breakdown of faith in the NPT.

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