Deterrence in the 21st Century

Written evidence from the United Nations Association – UK

‘Nuclear deterrence is sometimes treated as a known quantity – a definite thing that keeps us safe, and ensures our security. It has also often been used as a justification for possessing nuclear weapons. Nuclear deterrence, however, is based on an unexamined notion: the belief that the threat to destroy cities provides decisive leverage.’

Ward Wilson


1. No less a figure than Thomas C. Shelling outlined in 2006 the dual difficulty represented by deterrence underpinned by nuclear weapons: whether they deter, and the problems of use. Paraphrasing President Eisenhower, Shelling recounts the President, stating that "if nuclear weapons can be used for purely military purposes on purely military targets, I don’t see why they shouldn’t be used just as you would use a bullet or anything else." However, nuclear weapons lack offensive subtlety, and this challenges their efficacy as a deterrent and ultimately questions their potential use by a nation.

Limited Deterrent Value

2. In his foreword to the 2006 White Paper The Future of the United Kingdom’s Nuclear Deterrent, then Prime Minister Tony Blair stated that "an independent British nuclear deterrent is an essential part of our insurance against the uncertainties and risks of the future," and the White Paper continues this thread by reinforcing that the "Government’s primary responsibility is for the security of current and future UK citizens."

3. Yet the question must be asked, faced with a myriad of near certain short, medium and long-term international challenges, what does an independent nuclear deterrent bring to the table for a country that – as was shown by recent cuts in defence spending, including to every army infantry battalion – is already stretching itself thin? The United Kingdom has P5 status, it has a comparatively well-resourced and modern military, and the country is a top financial services hub and, with numerous overseas footholds from Diego Garcia to The Falklands, its imperial footprint, and the relative strategic advantage that this accords, is not entirely diminished.

4. But the UK is no longer a great power, as most decision-makers are aware, and yet it also struggles to match the prosperity enjoyed by citizens of other advanced economies. Many would argue that the United Kingdom must make a decision about which path it wishes to follow. According to CIA 2012 estimates, the UK lies 34th globally in terms of GDP per capita (taking into account purchasing power parity), and sits behind over two dozen nations on the United Nations Development Programme’s Human Development Index (HDI). Such indicators are coupled with long-term security challenges posed by a lack of surety over energy independence (as of 2012 only 43.1% of British energy came from UK sources – see, coupled with threats posed by, for example, climate change and cyber security.

5. As UNA-UK’s chair and former UK Ambassador to the UN, Sir Jeremy Greenstock, has commented on publicly (13 March 2013, International Institute for Strategic Studies), a range of factors contribute to the UK’s image and influence in the world. Amongst these, nuclear weapons capability is one of the least relevant. Ultimately, he states, the most important criterion for influence is a country’s economic strength, and the UK’s global influence comes from its: 1) association of relationships; 2) ability to manage those interests and relationships around the world; 3) capacity to solve problems in the international community in the various committees and councils; and 4) input into development and security in the developing world. An independent nuclear deterrent thus brings neither influence nor prosperity. It is equally limited militarily.

6. Today, and for the years ahead, the greatest direct security challenges that face the United Kingdom are represented by the uncertain asymmetric threats posed by various terrorist groupings, in addition to the instability of states within which, or near to where, the UK has resource interests. These frail states cannot be solidified by the UK’s nuclear deterrent, and the deterrent cannot be used as leverage or as ‘a big stick’ towards irregular forces within such states or in adjacent countries. Al-Shabab does not feel threatened by any state’s nuclear weapons, and the only time Al-Qaeda cogitates over any state’s nuclear deterrent, is possibly to consider how it might compromise the security of it. If, as the 2010 Strategic Defence and Security Review states, we require "a minimum effective security nuclear deterrent as the ultimate means to deter the most extreme threats," questions must be asked of the imagination of military planners who see nuclear weapons as the ultimate antidote to unseen, future challenges. Thirty-one years after Argentina invaded the Falkland Islands, the UK is without a carrier-based strike-force.

7. Within this multipolar world, a world that each day becomes more interdependent, it is difficult to see just how the UK’s independent nuclear deterrent retains the pre-eminence it does. In terms of political leverage, it is doubtful that it either solidifies the UK’s place on the UN Security Council (and even if it did, this would not necessarily be reason for retention) or helps sharpen the UK’s diplomatic hand with friends or foes to a degree that balances out the cost. The deterrent neither stopped an invasion by Argentina of The Falklands nor deterred Iraqi forces from invading Kuwait in 1990. The UK had significant interests tied up in both regions – territorial in the former and economically in the latter. It provides no extra strength in UN Security Council negotiations and, again, it is difficult to see what external threats it is currently set to counter.

8. If the argument "we don’t know what is around the corner" is utilised again and again for retention, it is virtually impossible for multilateral disarmament to take place, and thus create a more stable, secure world. The irony is that history has shown that nuclear deterrents the world over perpetuate conditions for insecurity through their presence and encourage proliferation by their existence. In the 2009 FCO policy information paper Lifting the Nuclear Shadow: Creating the Conditions for Abolishing Nuclear Weapons, the authors state that "Reducing and eliminating nuclear weapons without also addressing the balance of power in other respects could be dangerously destabilising."

9. Yet not considering openly what regional or global security contexts would be required to disarm the UK’s independent nuclear deterrent in the 21st century would be equally unwise. Who is to say that the retention of the independent deterrent perpetuates stability? Is it not equally true that many states globally will view the decision to renew as reason for them to seek to acquire?

Mass Destruction

10. A starting point for its retention and use must also imagine the situation where it might be used. A nuclear weapon is neither made nor capable of striking with pinprick precision or to affect limited collateral damage. Even the smallest nuclear weapons will have a devastating impact. For example, it is estimated that the smallest yield within warheads fitted to the Trident missiles probably lie close to the yields demonstrated by the British ‘Julin Bristol’ tests carried out in 1991 in Nevada, USA. This would be comparable to the first atomic weapon detonated over Japan in 1945 which killed tens of thousands of people directly. Any discussion of the deterrent must also envisage its use, and envisage the consequences of its use, and this raises questions of legality, morality and also begs questions of British democratic accountability.

11. The UK, as a state party to the 1949 Geneva Conventions, to both 1977 Additional Protocols and to the 2005 Additional Protocol III, is obliged to refrain from harming civilian populations, directly or indirectly. Specifically, Protocol 1, Article 51, paragraph 4 states that "Indiscriminate attacks are prohibited. Indiscriminate attacks are: (a) those which are not directed at a specific military objective; (b) those which employ a method or means of combat which cannot be directed at a specific military objective; or (c) those which employ a method or means of combat the effects of which cannot be limited as required by this Protocol; and consequently, in each such case, are of a nature to strike military objectives and civilians or civilian objects without distinction." This realistically pertains to any weapon of mass destruction.

12. It is highly unlikely that a nuclear attack, even with a relatively modest 10-15kt device, could be detonated without incurring significant civilian casualties. The United Kingdom has signed and ratified the Chemical Weapons Convention, which prohibits the storage or usage of any chemical weapons. It has denounced the use of such weapons by the regime in Syria, and yet the potential carnage that a nuclear weapon would unleash is much, much greater. A deterrent they may be, but they are not merely a chess piece stored in a closet.

Multilateral disarmament commitments

13. Discussions of deterrence must not be disassociated from disarmament. Supporters of the independent nuclear deterrent iterate that nuclear disarmament cannot be contemplated realistically until the global security backdrop is favourable. Yet who decides what is favourable? The international security context is unlikely ever to be idyllic: there will always be threats – certain, perceived and those that may exist ‘just around the corner’. The existence, threat of use of, and integration into strategy of nuclear weapons may even perpetuate or create some of these, and one detonation in anger or by accident will almost certainly change global diplomacy and warfare as we know it.

14. The virtual reaffirmation by the UK of its commitment to an independent nuclear deterrent represents a challenge to its disarmament commitments. The UK has made these commitments under the auspices of the 1968 Non-Proliferation Treaty (NPT) – repeated and reinforced in 1995 when the Non-Proliferation Treaty was extended indefinitely – which the United Nations Association of the UK (UNA-UK) urges the UK not only to uphold, but to promote internationally, particularly with other nuclear weapons states.

15. Article VI of the Treaty, for example, iterates that, "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." With a commitment to an independent deterrent, it is difficult to see how the UK can reconcile this with its commitments to the NPT, nor signal that it is in any way serious about nuclear disarmament, unilateral or multilateral.


16. The current UK government inherited the British independent nuclear deterrent from its predecessor and it from the government before. From government to government they have been passed since 1952 and, though the global stage has changed greatly, the nuclear weapons have changed little. Delivery systems have been altered or cancelled, or new ones have been designed, but the physics of a detonation remain unalterable, and this is reflected in the weapon. As nations’ militaries around the globe reform their assets to effectively confront multifaceted challenges, nuclear weapons retain a Cold War purpose from which they cannot escape – blunt and uncompromising.

We have inherited these things. The key question is: would we go out of our way to get them now if we didn’t already have them?



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James Kearney is Peace and Security Programmes Manager at UNA-UK. A member of the United Nations Association's delegation to the 2010 Non-Proliferation Treaty Review Conference in New York, James edits the organisation’s nuclear disarmament and non-proliferation briefing report series, chairs the London-based ‘Young Nuclear Professionals Group’ and is a frequent contributor to national and international print and online media. He has degrees from Oxford and Cambridge Universities and his doctoral studies at Edinburgh University examined societal reconstruction in post-Genocide Rwanda.

James Kearney

September 2013

(Contact: [email protected] or 020 7766 3446)


Prepared 20th November 2013