The U.K. Defence Review: A Nuclear Weapons “Credibility” Paradox

The U.K. government has announced plans to reverse 30 years of gradual nuclear disarmament in its Integrated Review of Security, Defence, Development and Foreign Policy, published on 16th March. Increasing the self-imposed limit on Trident nuclear warheads, from 180 to 260, is perhaps the policy document’s most eye-catching decision, though changes to the nuclear doctrine are also striking. Britain is now prepared, according to the review, to launch its nuclear weapons in response to a particularly ruinous cyber attack.

Over its 114 pages, the defence review also seeks to give substance to the government’s post-Brexit mission statement of a ‘Global Britain’, including a ‘tilt’ in focus to the Indo-Pacific. At the same time, Russia continues to be viewed as the most “acute threat to [Britain’s] security” and the army, although set to be reduced by 10,000, will be deployed more often to “train, exercise and operate alongside allies and partners across all [Britain’s] priority regions”. Across its analyses of global threats and proposed responses, the overriding theme of the review is one of military deterrence in place of diplomatic moral leadership.

Responses to this development in nuclear strategy, which bodes ill for hopes of non-violent resolutions to global conflicts, demonstrate the immediate knock to Britain’s international reputation as an advocate for nuclear disarmament. In the House of Commons, Opposition Leader Sir Keir Starmer accused the government of abandoning the pledges of successive prime ministers to reduce Britain’s nuclear stockpile without explaining “when, why, or for what strategic purpose”. A United Nations spokesman also expressed “concern” at the decision, which “could have a damaging impact on global stability”. Dominic Raab, the U.K. Foreign Secretary, cited the need to “maintain a minimum credible level of deterrent” as threats changed, describing nuclear weapons as “the ultimate insurance policy”.

While the planned expansion of Britain’s nuclear arsenal endangers multilateral disarmament, it is arguably the doctrinal change which poses the greater threat to peace. In addition to especially damaging cyber warfare, other “emerging technologies that could have a comparable impact” to chemical or biological weapons could also trigger a nuclear response. Any use of nuclear weapons would cause unthinkable horrors, and the defence review’s decision to increase Britain’s reserve represents only a minimal increase to the global stockpile which could be activated in the event of a first strike. On the other hand, by expanding the doctrinal justifications for the deployment of nuclear weapons, the U.K. government has worryingly changed the rules of the world’s most dangerous game. This is in contrast to Joe Biden’s America, where the new president suggested during his campaign that he considered nuclear weapons’ “sole purpose” to be deterrence, and if necessary retaliation, of a nuclear strike. 

A necessary element of a deterrence doctrine is a credible belief that the deterrence would be used as stated. In contrast to a nuclear strike, the defence review’s vague definition of new threats that justify launching Trident’s warheads leaves a measure of doubt. Such doubt over the credibility of threats brought the world to the precipice of nuclear war during the Cuban Missile Crisis. Now, by binding the nuclear threat to other modes of warfare the U.K. has imperilled the stability that developed to prevent a repeat of the events of October 1962. Certainty of a foe’s intentions enables a policy of ‘Mutually Assured Destruction’, but the defence review leaves the U.K.’s position open to interpretation.

The U.K. government has claimed that plans to increase its stock of nuclear weapons are necessary to maintain their credibility as a deterrent. Yet in the same policy document announcing this, the doctrine which articulates this deterrent has been obfuscated. The drafters of the review themselves seem not even to know what it intends to deter, since it refers primarily to future threats. How destructive must a cyber attack be to warrant the obliteration of a section of our planet and all who reside there? What threshold must a biological weapon meet for a nuclear holocaust to be deemed an appropriate response? We must all hope that the answers to such questions are provided in a policy document before the U.K. government finds itself hostage to the incoherent bellicose rumblings of this one, seeking to maintain their “credibility”.

Isaac Evans