Deterrence: no guarantee but essential

Deterrence is at best an art rather than a science. More realistically it is a strategy that depends on guesswork. Success is inherently uncertain. Why? Because in order to work as intended some culturally alien politicians must decide that they are deterred. They are quite at liberty to decide that they are not.

In short, the merit in a strategy of deterrence can only be decided abroad. This elementary truth is easily obscured by casual references to ‘the deterrent’, even ‘the nuclear deterrent’. Nothing, repeat nothing, is inherently deterring. In common with love and happiness, deterrence cannot be achieved or bought directly. Foreigners must decide whether Britain’s Trident force is or is not deterring. If we were to double the size of the force, it is unlikely that we would double the quantity of its deterrent effect.

Deterrence has come in for severe criticism of late. Some of the negative commentary is well targeted, but most has been wide of the mark. It is claimed that deterrence is becoming ever less reliable, as nuclear weapons proliferate to states whose values, interests, political practices and arrangements for weapon handling and control are unfamiliar to us.

This claim is sensible, though it errs in exaggerating the reliability of deterrence during the great Cold War of 1947-89. It will be forever unknowable whether we survived those years because of the genius in the deterrent doctrines and force postures of East and West, or simply because of luck. The notion that deterrence used to be reliable in the Cold War because each side understood the other is almost certainly a fallacy. Neither side really understood the other, as the archives now reveal but somehow we escaped the possible consequences of our and their ignorance.

An increasingly popular charge against strategies of deterrence is that they have been overtaken by strategic history. Specifically, if our future is to be populated strictly with irregular, which is to say non-state, enemies, deterrence allegedly is of little relevance. If those irregular enemies are adherents to a fanatic doctrine, so the argument proceeds, then they will not be influenced by the kind of cost-benefit analysis upon which our theory of deterrence has always rested.

It is claimed that terrorists, particularly suicide bombers, are beyond deterrence. For armed forces of any character to deter, they need suitable targets — access to some or all of the most valuable assets of the enemy. Should that enemy lurk incognito ‘amongst the people’, to quote Sir Rupert Smith (see his 2005 book, The Utility of Force), and lack vital fixed facilities, what can we threaten? How can deterrence possibly work? Can al Qaeda and its franchised off-shoots and imitators be deterred?

Fortunately, all is not doom and gloom, despite the largely valid claims just discussed. Terrorists, for example, are not beyond deterrence. They are deterrable by recognition of failure. Witness the history of the IRA. There are many reasons why terrorist organisations, movements, or ideas (it is not entirely self evident exactly what al Qaeda is at present) decline and effectively die, as they almost invariably do, but protracted lack of success is prominent among them. People are rarely enthusiastic about signing up with apparent ‘losers’. They are deterred by the belief that the terrorist group is going nowhere, achieving nothing, and is simply an exercise in futility. To die for a cause is one thing. To die for no good purpose is something else.

 So, a successful counter-terrorist strategy has a potent deterrent effect. Current terrorist spear-carriers defect, while potential recruits choose other ways to express their frustrations. Of course, there are people who cannot be deterred. Deterrence is not and can never be a ‘one size fits all’ panacea. Those people will need to be detained or, if necessary, shot.

To criticise deterrence is, by and large, to criticise the world the way that it is. A strategy of deterrence that relies on the threat of contingent action by nuclear and/or conventional armed forces, cannot provide perfect, total security for us. But, with its uncertainties and occasional irrelevance freely granted, deterrence still remains essential.

After all, it is so preferable to war that we can declare ‘no contest’ in that competition. The most sensible view to take of a strategy of deterrence is that it must be maintained for whatever uncertain value it will have. The fact that that value has to be uncertain is not a persuasive criticism. What is the alternative to deterrence? To cope with the inherent uncertainty of deterrent success we have to make some provision against its possible failure. In the Cold War the sheer scale of the rival nuclear arsenals rendered such provision futile. But that condition should not apply in this ‘Second Nuclear Age’ (see my 1999 book with that title) vis-a-vis any state other than the Russian Federation.

Will the 21st century witness a proliferation of ‘mad bombers’, of people, groups, and even states who are wholly immune to threats intended to deter? It is doubtful. There will certainly be some movements with a death wish, but suicidal strategies are self-limiting. Short of the truly undeterrable enemy, for example the group or state that actually wants to employ a nuclear weapon, deterrence is relevant but difficult.

 Contrary to popular imagery, the problem does not lie with irrational enemies who do not relate ends and means purposefully. They do not last long in politics anywhere. More probable, and therefore dangerous, are leaders who are rational but are unreasonable in our terms in the content of their rational goals.

Unless we can understand the political culture of the people we seek to deter, any success we secure by deterrence must be far more by luck than by judgment or even informed guesswork. This is why the US defence establishment has recently woken up to the need to comprehend the societies it needs to influence.

So what do all these rather abstract strategic arguments mean for the UK today? They are central to intelligent debate over the future of British defence policy. They demonstrate that policy cannot be satisfied by a strategy of deterrence alone because, as noted already, there will be occasions when deterrence is not relevant or is relevant but fails to deter.

They also show that for armed forces to deter they need to be competent at fighting. An army that ‘only does’ peacekeeping and the like is not going to deter enemies who are not risk averse. Such an army would need to be provided with protection by an army that is good at war fighting. To sum it all up, Britain has to seek to deter, or help deter (with friends and allies), what should be deterrable, while being ready to resist those threats that cannot be deterred.

What is the political and strategic context for all this? Perhaps the most troubling aspect of what passes for a defence debate in Britain at present are the confident assumptions held by some supposedly expert people, even though those assumptions are eminently challengeable.

Consider the still emerging debate over Trident’s replacement. This debate can only be conducted with a semblance of rationality on the basis of beliefs about Britain’s security context in the middle decades of the century. And what do we know about those? The answer of course is very little. What we do have is the benefit of 2,500 years of variably accessible history to alert us to the kind of events that we need to worry about. And we have our own experience and when all else fails there is always common sense.

A wise French thinker, Raymond Aron, advises that ‘prudence is the statesman’s supreme virtue’. Translated into advice for British policy, strategy, and defence planning, it means that we should strive to ensure that the mistakes we make today will be found to have been small rather than large in 20 to 30 years’ time.

We do not and cannot know what the strategic value of a British nuclear force will be in future decades, but we do know enough about the hazards of the twenty-first century to judge that it would be imprudent to discard such a force. Will Britain, or British forces, be in desperate peril in the future? We do not know. But we have some good grounds to suspect that the era of inter-state conflict is not over.

To be nuclear armed is to raise the threshold and the stakes for actual and potential enemies considering taking action against Britain and British forces, or multinational forces with a substantial British component. Bearing in mind the slow but apparently inexorable march of nuclear proliferation, so long as we engage in expeditionary warfare overseas our forces may well need all the deterrent cover possible.

Would we be willing to commit British forces to a campaign where the enemy, or the enemy’s close ally, is better (i.e. nuclear) armed than we are? Don’t worry, one may say, the Americans or the French will take care of nuclear deterrent duties. Will they? Everyone cares most for their own.

We do not know what British foreign policy will demand of its military instrument in the 2020s or 2030s. What we do know is that the world is going to become far more dangerous than it is today. There are six leading sources of danger:

• There is very likely to be a return of great power conflict, as Russia seeks to restore its pride, geopolitical position, and international standing

• As China seeks to protect its globally dependent economy

• As climate change acts like a ‘wild card’ and drives states to defend their national interests in the face of essentially unstoppable migration pressures, and emerging acute resource shortages

• As development continues to be hugely uneven between regions

• As the proliferation of Weapons of Mass Destruction (WMD), nuclear weapons in particular, are selected as weapons of choice in some regional quarrels; and, last and probably least

• As religiously motivated terrorism continues to harass the painfully slow process of modernisation in the land of Islam.

In such a world, which happens to be a plausible future for us, can we be certain that either on the defence — under threat — or on the offence, presumably in the company of allies, British interests of a vital character would be protected well enough by such deterrent effect as may be secured by American or French nuclear forces? Would the United States, or France, always be an active party to multinational policy and strategy that included Britain?

In the last resort, and that is the context under discussion here, states are self-regarding in their policy making. In the 21st century, a Britain bereft of nuclear arms would discover that its foreign policy goals needed to be disciplined dramatically. Nuclear-armed regional enemies would enjoy what we strategists call ‘escalation dominance’. That dominance could only be negated courtesy of the good offices of Americans and/or the French, neither of whom may be willing to place themselves in the nuclear line for issues closer to hearts in London than in Washington or Paris.

The future will be a very dangerous place. If Britain is to play a significant role in support of regional and international order, it must ensure that its armed forces benefit from whatever protection a modestly- sized national nuclear arsenal can provide. Deterrence is unreliable, indeed flawed, but nonetheless truly essential.

Dr. Colin S. Gray is Professor of International Politics and Strategic Studies at the University of Reading. He is the author of more than twenty books, including ‘Another Bloody Century: Future Warfare’ (Phoenix, Orion Books, 2006, £9.99).