Big enough to deter

Letters

Vol. 4 No. 8 · 6 May 1982

From Solly Zuckerman

SIR: I am sorry that your reviewer, Mr McMahan, interpreted my reference to the concept of minimal deterrence as implying an ‘absolute’ measure of the size of a nuclear arsenal (LRB, 15 April). The engaging sophistry with which he treats the issue, and then provides his own answers, would, I imagine, apply equally to the apocryphal question of how many angels could dance on the head of a pin. It also reveals a certain remoteness from the real world and some innocence about the technical and military realities of nuclear armaments.

Lest what he has written mislead any of your readers into supposing that the numbers and kind of nuclear arms that are possessed by the nuclear powers have been produced in the fulfilment of rationally-formulated operational requirements, let me, as one who has been directly involved in the process, assure them that this is not the case. Nor is it the case that one country’s idea of what constitutes an adequate armoury is determined by the example of another. At the time of the Cuban missile crisis in 1962, the number of warheads in the arsenals of the USA and the USSR was a fraction of what they have now. There were, however, enough to deter both sides from starting a nuclear war, given that either, at any time, had thought of doing so. In relation to what exists now, those numbers constituted a level of, let us say, minimal deterrence.

The United Kingdom then also had a sizeable arsenal, but what use it would have been, given that hostilities had broken out, no one knew. We were at the ringside of the dispute, into which we would have been inevitably drawn if it had not been defused. Had the Russians not given way, it was expected that what was called ‘the nuclear balloon’ would go up on Sunday, 28 October. As I recounted in an obituary of Lord Mountbatten, he, our three Chiefs of Staff, the Permanent Under-Secretary and myself (then Chief Scientific Adviser) were together with the Minister of Defence, Mr Thorneycroft (now Lord Thorneycroft), when we learnt that the Russians had accepted the Americans’ terms and that the crisis was at an end. We just sat round the table looking at each other, until the silence was broken by Lord Mountbatten, with the remark: ‘Well, what would we have done if the Russians had not pulled back: do we know?’ No one knew, and no one has yet provided an answer. Somehow I doubt that one has been produced by Mr McMahan or by any of his fellow research students.

Mr McMahan tells us with categorical assurance that a nuclear arsenal of the size which the United Kingdom possesses ‘would not provide a credible deterrent to such threats as the destruction of shipping or a limited conventional attack’. What the source of this presumed piece of military wisdom is, he does not indicate; I cannot believe that it derives from his own experience. The critical fact is that no direct ‘limited conventional attack’ has taken place from either side since Nato was formed. None occurred in the 1950s, when Nato’s total arsenal in terms of destructive power could not have been much in excess of what the UK disposes now. If the Russians had wanted to invade Nato territory then, would they not have been deterred by féar of a nuclear riposte, whether or not this would have happened? Was the Nato nuclear armoury not a ‘credible’ deterrent then? What, in fact, does ‘credible’ mean in Mr McMahan’s vocabulary? Does the fact that a nuclear exchange today would result in vastly more devastation than it would have done twenty years ago make the nuclear threat and counter-threat more credible? Mr McMahan confuses me. Happily, however, there is a grain of comfort in the knowledge that when it comes to action, military commanders and planners are not governed by the post hoc rationalisations of armchair strategists. Everyone in a position of authority and responsibility on both sides has known for years that a direct armed confrontation between the Western and Warsaw Pact powers must be avoided because of the risk that it could trigger a nuclear war.

One final point. Mr McMahan writes as though it is not my view that one or other of the two superpowers could start unilaterally reducing the size of its enormous nuclear arsenal before the two engage in what is called ‘balanced reduction’. This is not so. As my book makes clear, I do believe that this could be done, at the same time as I hold that neither of two nuclear-armed adversaries could in reason divest itself of its nuclear weapons to the level at which the other side could use the threat of a nuclear attack as an instrument of political policy. What this level would be is anyone’s guess, but knowing something about the nature and repercussions of destruction in war, I would settle, as I suggested, for enough destructive power to guarantee, say, the devastation of ten of the UK’s, or the USSR’s, or the USA’s, or France’s main cities. But that, of course, is a personal view, not the result of some abstruse and ‘objective’ calculation, or of some academic exercise of logic applied to terms which are dealt with in a manner that denies them any military or political reality.

Solly Zuckerman
Lord Zuckerman, University of East Anglia

Vol. 4 No. 9 · 20 May 1982

From Jeff McMahan

SIR: Lord Zuckerman’s reply to my review (Letters, 6 May) unfortunately shares the faults of his book: his comments are both confused and inconsistent. He first criticises me for suggesting that his notion of minimal deterrence implies ‘an “absolute” measure of the size of a nuclear arsenal’ – meaning, I suppose, an absolute measure of what size a nuclear arsenal ought to be. He then suggests that to seek such a measure is analogous to attempting to determine how many angels can dance on the head of a pin. He concludes his letter, however, by giving it as his ‘personal view’ that a nuclear arsenal should have ‘enough destructive power to guarantee, say, the devastation of ten’ of an adversary’s main cities. Given the sense of the term ‘absolute’ as it is used in my review, that estimate has all the signs of an absolute measure. (I will yield to any intuitions he might have about his analogous problem with dancing angels.)

He next accuses me of misleading your readers into believing that the world’s nuclear arsenals have been produced to fulfil rational policy requirements. I never implied that this was so, though I suppose it is implicit in my piece that it would be, nice if it were so.

There then follows an interesting but doubtfully relevant anecdote which features Lord Zuckerman at a pow-wow of VIPs during the Cuban missile crisis. The parade of big names with whom his Lordship was intimate leads gracefully up to his sneering reference to my being a mere research student, but neither the anecdote nor the sneer does anything to advance the argument of his book or to rebut my criticisms.

It is curious that he then goes on to defend with great vigour the view that nuclear weapons could be useful for deterring a limited conventional attack by a nuclear-armed adversary. In his book he writes that ‘if anything is going to inhibit the Russians from making any incursion into Nato Europe, it will be Nato’s conventional forces.’ His abandonment of the view put forward in his book will disappoint some of his admirers-in particular, Professor Michael Howard, who has recently praised him in the TLS for adhering ‘to the good old view… that nuclear weapons are good for nothing except neutralising other nuclear weapons.’

Finally, he complains that I do not give him credit for believing that each superpower could make unilateral cuts in its arsenal, and claims that his book makes it clear that this is his view. But the only references I can find in his book are to bilateral reductions. And in any case I explicitly note that it is implied by his argument that either superpower could make cuts unilaterally.

All this, however, is rather beside the point: nowhere in his lengthy and dismissive reply are my central criticisms of his book addressed.

Jeff McMahan
St John’s College, Cambridge