By Jenny Nielsen, Research Analyst, Non-Proliferation and Disarmament Programme

The debate on the future of the UK’s submarine-based Trident nuclear-missile system continues, with a broad spectrum of views on the role, postures and relevance of this system in the twenty-first century. The Trident system and the notion of the UK’s deterrent are arguably overdue for some semantic ‘conscious uncoupling’. 

Last week, the House of Commons Defence Committee published its eleventh report entitled Deterrence in the twenty-first century. Among its conclusions, the Committee argued that ‘deterrence, both nuclear and conventional, has an important place in the defence philosophy of the UK but will increasingly form part of a more complex security strategy alongside greater need for resilience and recovery as the world becomes more multi-polar and less stable and where the certainties of identifying an aggressor may be reduced’.

The range of differing views on Trident’s future was all too evident in the exchange of arguments by a panel of distinguished parliamentarians at the IISS discussion meeting held a fortnight ago. One year on from the discussion panel on the foreign policy implications of a decision to replace Trident’s submarine-based nuclear-missile system, four parliamentarians tackled key issues that the UK will have to address leading up to the 2016 ‘main gate’ decision. Following the July 2013 publication of the Trident Alternatives Review (TAR), and ahead of the May 2015 general election, this proved a timely point to address salient questions that have not yet been fully aired, including on the role, system options, deterrence postures and opportunity costs.

Role – ‘ultimate insurance policy’ against uncertainty

Whilst Dr Julian Lewis MP and Admiral Lord West of Spithead argued that the UK’s Trident system remained the ultimate insurance policy against uncertain future military threats and nuclear blackmail, the other two panellists disagreed about the role and continued relevance of Trident. Baroness Shirley Williams of Crosby perceived Trident as the Maginot Line – ‘outdated’ – arguing that new threats, like cyber warfare, are of greater priority and relevance in today’s security environment, as evidenced in Estonia. Sir Nick Harvey MP emphasised that the UK should retain its nuclear know-how and capability for addressing potential future existential threats – should a nuclear adversary with both intent and capability arise – but that a new, non-continuous at sea deterrence (CASD) posture for the system should be adopted. Harvey added that it is debatable whether Trident is fulfilling any practical utility at all.

Diverging threat perceptions amongst the panellists punctuated the arguments. Whilst Harvey argued that there is a greater prospect of Britain being hit by a meteor than a nuclear warhead, Lewis and West argued that threats are unpredictable, stressing uncertainty about unforeseeable risks to Britain. The Defence Select Committee concluded that ‘while the potential range of emergent threats is significant, they do not preclude either the re-emergence of tensions with an existing nuclear power, nor the emergence of a new power whose interests are inimical to those of the United Kingdom with the capacity to deliver a CBRN attack on the UK or its interests’. 

CASD alternatives in a post-Cold War milieu? 

The question that Britain’s next government faces is essentially whether to CASD or not to CASD. The debate in the UK amongst the three major political parties has not yet got past this point, despite the UK being the most progressive of the five NPT nuclear weapon states vis-à-vis Article VI commitments. Russia’s recent annexation of Crimea, and other potential scenarios in which threats can arise unpredictably and quickly, were raised by Lewis as an argument for the continued need for a credible nuclear deterrent system. Both Lewis and West argued that a credible system would consist of a CASD posture. Lewis argued that opting for a non-CASD posture for Trident or a ‘part-time deterrent’ would be ‘the slow boat’ towards unilateral disarmament. From an operational perspective, West stressed the importance of deployment for the survivability of the UK’s Trident system. 

Harvey argued that patrolling 24/7 in the post-Cold War security environment simply makes no sense as the UK currently has no nuclear adversary with both the intent and capability to threaten Britain. He further stressed that credible alternatives exist (as concluded by the TAR) and that Britain has a whole ladder of nuclear possibilities, some of which would be welcomed internationally. West disagreed and warned that moving down the nuclear ladder unilaterally would be politically damaging to the NATO alliance and unwelcome in many European capitals.

The Defence Committee concluded that ‘the assessment of future threats is as important as the assessment of current threats in considering the case for the nuclear deterrent’. Furthermore, the Committee argued that ‘nuclear proliferation is not under control and many of the sources of future insecurity could in themselves contribute to state-on-state conflict, creating an ever more unstable, and increasingly nuclear-armed, future strategic context’. 

Opportunity costs

West argued that the funds allocated to Trident (roughly 4% of the defence budget) are not a high premium to pay for the ultimate security blanket. He further clarified that opting for a non-CASD posture would not solve the issue of scarce conventional military resources; those believing that any earmarked Trident funds would otherwise be allocated to other defence purposes are delusional. The Defence Committee’s report on deterrence weighed in on the opportunity cost of the nuclear deterrent, warning that ‘it would be naive of us to assume that a decision not to invest in the nuclear deterrent would release substantial funds for investment in other forms of security’. Furthermore, the Committee recommended ‘the decision on the retention of the nuclear deterrent, and whether its retention is still merited as a means of deterring existential threats to the UK, should be made on its own merits, rather than on the basis of what else could be bought with the money saved’. Echoing this sentiment, West stressed that some things are more important than costs.

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