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The following lecture by Sir Michael Quinlan on the ethics of nuclear deterrence was given on 14th February 2008 at the Jesuit church in Mayfair as part of an annual series.  CCADD members are encouraged to read it and to comment on it if they wish.  The CCADD website exists to promote debate on questions such as Sir Michael raises in his talk, and he is happy that his lecture can be made available for this purpose.



Farm Street Talk

14 February 2008




Michael Quinlan


Every human activity must be subject to ethical scrutiny – moral accountability is a central part of what it means to be human.  The activity of war, and the use of its weapons, cannot be an exception.  But it has always posed special ethical problems, because all weapons are humanly appalling – they are designed to kill people, and their ghastly efficacy in that has mounted steadily throughout history.  In 1945, however, there was a dramatic step-change, horrifyingly manifested at Hiroshima and Nagasaki.  The memory of what was done to those cities will remain vivid for ever.  Nuclear weapons can kill and destroy on a scale, and with a certainty and immediacy, utterly beyond all earlier experience.  They take the potential of all-out war between advanced states over a cliff-edge, into lunacy – they generate indeed its reductio ad absurdum.  The technological revolution which they embody has thereby set problems which long-established frameworks of ethical analysis find hard to handle, rather as in the medical field the ability of technology and scientific understanding to do things previously unimagined poses new moral dilemmas.


The prime conceptual apparatus which I seek to bring to bear in moral evaluation is the stream of thinking which we know as the Just War tradition.  Nuclear weapons have difficulties with two of that tradition’s tests for legitimately going to war – jus ad bellum and with two of the tests for how war can be conducted – jus in bello.  The jus ad bellum problems concern how any war in which nuclear weapons are used could have reasonable prospect of success, and how it could be proportionate – that is, how the war as a whole could ever be expected to do more good than harm.  The jus in bello problems concern how any particular use of nuclear weapons could satisfy the tests of being discriminate – not deliberately attacking the innocent – and proportionate – again, not doing more harm than good.


In face of these grave moral difficulties there are basically three potential ethical stances available to be adopted – and ultimately only three, though variants of their practical application are possible:


Position I maintains that it is morally imperative always and unconditionally to renounce the possession of nuclear weapons, regardless of circumstances and consequences.


Position II maintains that the use of nuclear weapons must be always and unconditionally renounced, regardless of circumstances and consequences; but that the possession of them for deterrence – to prevent major conflict of the World War I and II kind, which has been their prime objective and their successful effect since 1945 – can be morally tolerable if it is reasonably judged effective and necessary for that aim.


Position III maintains that some use of nuclear weapons, in ways and on a scale the prospect of which could provide effective deterrence, just might in extreme circumstances be morally tolerable; and that their possession for war-prevention can therefore be legitimate.


Every one of these Positions faces difficulties so severe that, taken in isolation, they would normally have to be regarded as conclusive against it.  But there is, in inexorable logic, no fourth basic position available.  The internationally-distinguished Quaker Sydney Bailey once wrote that there was no policy about nuclear weapons that did not pose appalling moral and practical dilemmas.  The ethical analyst has no alternative but to choose one of these positions, deciding which of them poses least difficulty.  It follows that in any honest debate about the choice it is not legitimate to focus exclusively upon the objections to the positions rejected.  The objections to the position preferred must also be candidly acknowledged and tackled.  All this is a reflection of the perplexities and dilemmas set by the reductio ad absurdum of war which the advent of nuclear weapons generates.  Let me sketch some of the difficulties for each of the three stances 


The absolutist Position I claims to prohibit nuclear-weapon possession for all time and in all circumstances, whatever new and painful lessons history may inflict.  It must therefore accept being tested against awkward and perhaps extreme scenarios.  It cannot escape by claiming that such scenarios can be guaranteed not to materialise if wise decisions are taken in good time.  History demonstrates that human affairs can go gravely amiss, and decision-makers cannot absolve themselves from facing up to hard practical questions on the ground that they would not have arisen if only someone or other had done something different and wiser beforehand.  Position I has to be prepared to say that even if it had been known during the Second World War that Nazi Germany was successfully developing nuclear weapons, it would have been the unconditional moral duty of Churchill and Roosevelt not to try to match that capability.  It has to be prepared to hold that during the Cold War it was the unconditional moral duty of the West to discard all its nuclear weapons even if the Soviet leaders refused to do so, kept all their own nuclear weapons and were thereby in a position to impose their will by overwhelming force or the threat of it right across Western Europe or anywhere else they wanted.  It has to be prepared to maintain that it is the unconditional duty of Israel to give up the nuclear weapons which everyone knows her to possess even if hostile countries around her, like Iran saying in the words of President Ahmedinejad that she ought to be wiped off the map, were to come to have massive military preponderance including nuclear weapons.  It has to hold that even if we believe that nuclear weapons have conferred an enormous benefit for over sixty years by ruling out the top level of great-power warfare, and that the risk of that happening again with all its fearful costs to everyone would have been and might still be much higher without them, they must nevertheless be unconditionally and if necessary unilaterally renounced.


These examples bring out the fundamental difficulty for Position I.  It amounts in the end, in face of any adversary who possesses nuclear weapons and may have the will to use them, to full-blown pacifism – to abjuring recourse to arms and indeed to any other form of resistance, however appalling the character, record and actions of the adversary may be.  As even the deeply-embattled Japanese leadership recognised in August 1945, no lesser type of resistance can hope to stand against nuclear weapons.  There have sometimes been efforts to portray passive dissent or non-cooperation of one kind or another as potential alternatives to complete submission, on the pattern for example of Mahatma Gandhi’s leadership of opposition to British rule in India between the two World Wars.  But that rule, for all its imperfections, was not that of Hitler or Stalin either in inhumanity or in willingness to enforce obedience brutally.  There can be no reality in hopes that non-violent resistance can plausibly offer a universally effective answer to the problem of how to protect peoples in the face of nuclear weapons in hostile hands.


Position II – “use never allowable, but possession for deterrence potentially permissible” – has obvious having-it-both-ways appeal, and it would be nice to be able to espouse it – Cardinal Basil Hume, to my direct knowledge, was much drawn to it in the 1980s.  Alas, however, it is fundamentally incoherent - a claim to square a circle.  While deterrence and use are different, they cannot be totally disconnected.  Weapons deter by the possibility of their use, and by nothing else.  If there is no possibility of use, there is no deterrence.  Position II envisages the deliberate creation of a fearsome capability which it maintains must never be used; and at the same time it makes a renouncing statement about use which it has to hope will not be believed.  The whole concept must amount to the calculated expression of a massive untruth: either the preparation – requiring massive numbers of people to commit their working lives to demanding tasks - is bogus, or the renunciation is insincere.  The nature and positive intent of each component is to convey a message directly contrary to that purportedly given by the other - the concept seeks deliberately to imply what it explicitly denies.  We simply cannot accept such a stance as resolving a profound moral dilemma.  – even if, very questionably, we thought that it would work in practice for war-prevention.  The attempt is understandable to avoid the bitter choice between abandoning war-preventing deterrence and allowing nuclear use to be potentially legitimate; but it fails.  Position II simply falls apart under scrutiny.  There is no way of evading the hard basic choice between Positions I and III.


The central difficulty for Position III is to explain how any use of nuclear weapons could ever be consistent with the Just War imperatives I mentioned earlier.  I take first the jus ad bellum aspects.


In a nuclear war, Ronald Reagan notably said, there would be no winners.  This is true in the sense that any substantial nuclear exchange would leave both sides worse off than before.  But that was true also of World War II, not least for Britain, yet it was clear then that there were victors and that we were among them.  The comparison that has to be made is not between before and after – it is between the future “if we do” and the future “if we don’t”.  The use of nuclear weapons in conflict could take many forms other than that of wholesale launch-everything world-destroying exchange, and escalation to that is not in the least certain.  We do not have to exclude entirely and for every conceivable scenario the possibility that the use of nuclear weapons could serve to bring an aggressor up short and deny him the attainment of intolerable aims – that was a key element in NATO’s concepts during the Cold War - and so could lead to an outcome that might legitimately be classed as successful, for all its bitter costs, and as worth those costs (that is, as proportionate).  Escalation to intolerable levels is always a risk, and would have to be weighed most gravely; but the burden of possible fearsome consequences would loom over both sides, not one alone.  The risk of escalation cannot mean that there is always a unilateral and unconditional duty upon one side, in every possible situation, to offer no adequate resistance, or no deterrent prospect of such resistance, to a nuclear-armed opponent.


For those who take Position III the sharper ethical difficulties arise on those jus in bello criteria – discrimination and proportionality.  Before I attempt to deal with them, however, let me do a little more explanatory scene-setting.  Taking Position III does not mean approving everything that was done during the Cold War, or everything that is still being done now.  The nuclear armouries in the Cold War became grotesquely excessive, and there is no doubt that some of the planning for their use, on both sides, would have been morally intolerable to execute in any circumstances whatever.  Position III, moreover, does not entail having a fixed and implacable intention to use the weapons automatically or wholesale in some defined scenario; it requires no more than acceptance that in some extreme setting it just might become legitimate to use them.  It would not be incompatible with Position III to express one’s approach as being an initial presumption against any use.  And it is entirely possible also to hold Position III and still think, as a matter of practical prudential judgment, that Britain, or indeed everyone, ought to discard their armouries now that the Cold War is over.


My view of the practical moral imperatives under Position III has three components:


            First, we should make the contribution which these terrible weapons make to preventing major war as secure, as stable and as little demanding of resources as we can.  Though much has been done in this direction since the Cold War, there is still a substantial further agenda available.


            Second, in our provision and shaping of nuclear forces and our contingency planning for their possible use in dire emergency we should do the best we can, consistently with maintaining deterrent adequacy, in the direction of conforming to those criteria of discrimination and proportionality.  Our concept of use should be firstly to stop the conflict by demonstrating its fearful dangers, and then - if we are still pushed to it - to impose upon the offending adversary regime (the regime, not the people) as heavy a price as seems necessary to halt its offence or to make resumption or repetition unlikely, while keeping to the lowest practicable level (appalling though that would still almost certainly be) the damage done to the innocent – in shorthand, killing as few non-combatants as possible, not as many.  The British Government has never said much about its targeting concepts, but when it first decided to acquire Trident, back in 1980, the explanatory document spoke of posing a threat to “key aspects of Soviet state power”.  France, which once had an openly counter-city counter-population philosophy of a kind that I would have regarded as morally indefensible, has moved more recently in the same direction, and so did the United States a good many years ago.


Now I well realise that all this is not an easy moral position to sustain, given the awful realities of what nuclear weapons inescapably do.  The argument is at full stretch.  But that is true, at some point or another, of every other possible stance; and I regard its difficulty as ultimately less severe than the enormous central difficulty of Position I.  Position III seems to me in line with the underlying pragmatic and prudential philosophy of the Just War tradition, which has noted that absolutist prohibition of effective resistance would, in the words of Vittoria, one of its key developers in the sixteenth century, make it “impossible to wage war against the guilty, thereby prohibiting the just side from fighting”.  More recently, Gaudium et Spes, the great utterance of the Second Vatican Council on the Church in the Modern World, said that “As long as the danger of war remains and there is no competent and sufficiently powerful authority at the international level, governments cannot be denied the right to legitimate defence once every means of peaceful settlement has been exhausted”.  It is hard to suppose that the right to legitimate defence absolutely excludes what in extreme situations might be the only effective means available for it.


Some commentators on the ethical problems of nuclear deterrence in effect give up, holding that one is driven to “an ethics of distress”, as meaning that the whole problem is so intractable ethically that the attempt to apply normal or general moral rules must simply be abandoned.  That counsel of despair comes near to saying that moral evaluation must just throw in the towel when the going gets really tough, and it could be taken to mean that anything then goes.  I believe that the right near-term course must be to do the best we can, short of destroying deterrence, in the spirit of the moral criteria.  That approach has potential implications not only for ideas about targeting but also about weapon numbers, accuracy, explosive yields, readiness and the like. 


But I come now to the third imperative.  However firmly one may believe, as I do, that Position III is the best and indeed – for those who bear responsibility for the protection of the people - the inevitable basic stance, the whole situation with its fearful dilemmas is, on a long view, plainly unacceptable.  The 1981 Defence White Paper included these words:


            “No-one – especially from within the ethical traditions of the free world, with their special respect for individual life – can acquiesce comfortably in [nuclear deterrence] as the basis for international peace for the rest of time.  We have to search unremittingly, through arms control and otherwise, for better ways of ordering the world.”


That is a task that must surely be kept always in view.  There is more serious study work going on now about it, on both sides of the Atlantic, than for a long time past.  Abolishing all nuclear armouries would be a massive and hugely complicated business in technical terms alone, and it would need moreover a changed world-wide political environment, a shared understanding and a common political will which do not exist today.  As that White Paper went on to say, “The search may be a very long one… and impatience would be a catastrophic guide”.  It is vacuous to suppose that nuclear weapons are pointless and can be given up as a sort of international equivalent of giving up smoking.  Moreover, to demand that negotiations for abolition should now be started swiftly is as realistic as it would have been in the 1970s to demand that negotiations be embarked upon for the demolition of the Berlin Wall.  To demand negotiation for which the political conditions simply do not yet exist is mere posturing.  But there is genuine work to be done on identifying the conditions that would have to exist and the mechanisms that would need to be put in place, and on getting as much international understanding of all this as possible.  It is to the credit of the present Government that it is putting significant resources into the effort.


Finally, I offer some comment on the stance of the Catholic Church on these issues.  I have been in the uncomfortable position of maintaining publicly that the Scottish Bishops Conference has been misrepresenting that stance.


In June 1982, in a major prepared statement to the United Nations Special Session on Disarmament, Pope John Paul II said this:


            “In current conditions deterrence based on balance, certainly not as an end in itself but as a stage on the way towards a progressive disarmament, can still be judged morally acceptable.”


It is beyond doubt, both from the context and from subsequent exegesis by his Secretary of State, that nuclear weapons were in his mind.  We cannot establish for certain whether he held what I have called Position II or Position III, but it is incontestable that he did not hold Position I.  The United States Catholic Bishops also plainly did not hold Position I (or Position II, for that matter), nor did their French or West German counterparts.  The Bishops of England and Wales, after long deliberation involving diverse experts in a way not paralleled north of the Border, took up no definite public stance.  The Scottish Bishops however espoused Position I, which they have staunchly maintained ever since.  They were accordingly clearly at variance with the Pope (though I am not aware that they have ever publicly acknowledged this), and by inevitable implication they did not regard his utterance, despite its high-profile character, as constituting authoritative teaching rather than just an opinion or view.


As the 1990s progressed the Vatican, largely though not only in the person of Archbishop (now Cardinal) Renato Martino first in New York and then in Rome, increasingly urged that all nuclear weapons be got rid of.  In his New Year message of 2006 Pope Benedict made clear that he was of that mind.  He said that the idea that nuclear weapons could contribute to security was “completely fallacious”.   I respect what he said, though I do not agree with it (just as the Scottish Bishops did not agree with what Pope John Paul said in 1982).  But Pope Benedict’s assertion in any event expresses a judgment about practical effects in the world, not a pronouncement of theological or ethical principle on which the Vatican has special expertise and standing.  It is an opinion which can perfectly well be held in the post-Cold-War world by an adherent of Position III.   It is moreover not incompatible with what Pope John Paul said in 1982, because it can reflect a judgment about changed circumstances in the world since then.  For Pope Benedict to take up the absolutist anti-nuclear Position I, however, would have entailed a direct repudiation of what Pope John Paul, as well as those major Bishops’ Conferences, had conveyed.  So striking a reversal could be believed to have taken place only if there were an explicit statement or other unmistakable and cogent evidence to that effect.  No such evidence exists. 


I have no quarrel with the right of the Scottish Bishops personally, or of any Catholic, to hold Position I, on the tenable basis that the Church’s magisterium has not definitively adopted any one of the Positions.  But to claim that Position I is the clear and consistent – consistent - teaching of the Church (and Cardinal Keith Patrick O’Brien has drawn a sharp distinction between such teaching and mere opinions of the Holy See) is plainly mistaken.  The Catholic Bishops of England and Wales, after again inviting and listening at first hand to different viewpoints, expressed a preference as a matter of judgment that Britain should set an international example by not continuing as a nuclear-weapon power; but they refrained from taking their stand on any absolutist ground.


Throughout this field formidable problems beset any view, and it is the duty of us all both to recognise difficulty and face up to it honestly, and to listen very carefully to one another.