But where are all the anti-nuclear protesters? Why have there been no marches, no pamphlets, no anguished protests from writers and artists? Have 50 years of intermittent campaigning for nuclear disarmament been no more than play-acting? And has bien-pensant opinion not noticed that, in terms of the likelihood of nuclear war, the world today is more terrifying than ever?
Since Hiroshima, anxiety about nuclear weapons has gone in cycles. The immediate reaction to the first bombs was not only relief on the part of those who were fighting, or about to fight, against Japan, but jubilation. For a time, one London paper dated its numbers by "Days of the Atomic Age". But then came a long lull.
It wasn't until the late 1950s that "nuclear disarmament" became an active cause. Forty years ago last Easter the Campaign for Nuclear Disarmament first marched from London to Aldermaston (subsequently the other way round). You need to be the wrong side of 50 to remember the Manchester United air crash, the death of Buddy Holly - and the words of "Och, och, we're off to Holy Loch", or "Strontium 90, strontium 90, falling all around".
We marched behind Bertrand Russell and Canon Collins from a variety of motives: partly because it was the fashion, partly to meet friends, partly, perhaps, in the hope of meeting a nuclear disarmer of the opposite sex who might want to share one's sleeping bag. And because we didn't want to be incinerated. There was a good deal of naivety about CND then, but there was also sincerity and good faith, a contrast maybe with later peace movements.
Within 10 years, the movement had declined. Protesters now raged against the American war in Vietnam - conducted with great brutality but with "conventional weapons" - and whatever 1968 was about, it wasn't principally about nuclear disarmament. Here, there was more than one reason for that decline.
The Cuban missile crisis in October 1962 had demonstrated that, for one thing, with all their ferocious antagonism, the Americans and Russians would always draw back from the brink of mutual annihilation. And for another, it had shown that the "independent nuclear deterrent", about which the Tories boasted for so many years, and over which Labour agonised almost to the point of internal destruction, was completely irrelevant.
That lull lasted until the late 1970s and early 1980s, when nuclear disarmament became once more a fashionable cause. The Marxist historian E P Thompson took over from Canon Collins, while Michael Berkeley composed Or Shall We Die, an anti-bomb oratorio to a text by Ian McEwan, and Martin Amis published Einstein's Monsters. Looking back, there is no logical reason why a peace movement should have reappeared then. Nuclear war wasn't objectively more likely in 1981 than in 1971, and there was, this time around, a hint of bad faith, an element of attitudinising, and some dubious motives.
Twenty years earlier, cold warriors had claimed that CND was a Communist front. It wasn't that, though I count as part of my own political education noticing, in Easter 1961, that I was marching between the banners of the Hackney and Hampstead Communist Parties. Nor was the later peace movement merely another Communist front, although the newly opened Moscow archives embarrassingly show that the Russians did indeed take a close interest in it. More than that, the movement was premised on an egregious form of "moral equivalence". When the sainted Edward Thompson said that "Western Europe has got to get out from under American domination, just as East Europe must get out from under the Soviet Union," you didn't have to work for the CIA to see he was not comparing like with like.
That isn't the only way the 1980s peace movement seems unimpressive. Martin Amis claimed that nuclear weapons were "clearly the worst thing that has ever happened to the planet ... They distort all life and subvert all freedoms." And he couldn't "help wondering how it might be" if a nuclear warhead hit London. "Suppose I survive. Suppose my eyes aren't pouring down my face ... I shall be obliged ... to retrace the long mile home, through the firestorm, the remains of the thousand-mile-an-hour winds, the warped atoms, the grovelling dead. Then - God willing, if I still have the strength, and of course, if they are still alive - I must find my wife and children and I must kill them.
"What am I to do with thoughts like these?" What indeed? It seems almost unfair to dig out that ludicrous passage now, but people took it seriously then. His obsession with nuclear weapons had been produced, Amis explained, by the experience of becoming a father for the first time, and by reading Jonathan Schell's book The Fate of the Earth, adding obliquely, "I don't know why he is our best writer on this subject." Nor do I. Actually, The Fate of the Earth is one of the most fatuous books ever written. But it was an important text in the anti-nuclear story, and took chattering New York by storm, if not firestorm, in 1972.
Those books came and went, and so did the Cold War. But nuclear weapons are with us still. Yet where are the nuclear disarmers today, when we need them quite as much as ever? With all its gruesome balance of terror and mutually assured destruction, the Cold War worked, twice over.
Then see what has happened since, all unnoticed by chattering classes and youthful idealists. Our world has grown ever more dangerous, in terms of the likelihood of nuclear war. No one knows for sure which of the successor states of the Soviet Union possess warheads, or how many, or for what purpose.
Disarmament itself carries its own penalty. It was plausibly said that a superpower arsenal of 4,000 warheads was insane. So it may have been. But a world where there are only 40 warheads would be much more frightening, because they would be more likely to be used. After all, the only time that nuclear weapons have been fired in anger was when just two of them existed.
For decades India and Pakistan have been conducting their own cold war, which has sometimes flared into a hot war. And it was during one of their confrontations a few years ago, when an Indo-Pakistani war seemed imminent, that I was struck with horror of a kind I don't think I ever felt on the road from Aldermaston more than 30 years ago. For the first time since 1945, we were living in a world where nuclear weapons not only existed but were possessed by countries seriously prepared to use them. Israel has had them for years, and, as her gung-ho supporters even boast, is ready to fire them at Teheran and Baghdad, should Iran or Iraq attack Tel Aviv with chemical missiles. Or Shall They Die - maybe millions of Indians or Iraqis? And do we care?
I was conceived before the first atom bombs were exploded, and have lived my life supposedly in the shadow of annihilation which never came. Now for the first time I believe that we may see nuclear weapons used in war. That, and not the superpower deterrents which did in fact deter, would be the worst thing that could happen to the planet.