The prediction made by right-thinking individuals during the 20th century that proliferation would be an inevitable consequence of the existence of nuclear weapons has come to bear.

Those states with nuclear weapons are upgrading, replenishing and replacing their stocks, while those without them are increasingly weighing up the benefits of joining this elite (or I should say notorious) club of nations.

We may still occasionally kick up a fuss about the gradual subversion of the idea of a nuclear-free world, but bolstered by the fact that nuclear weapons were never used during the Cold War, realist political theorists have successfully popularised the idea that the more states that possess the bomb, the less likely war becomes. Like the car or the internet, we have come to accept nuclear weapons as an everyday part of civilisation.

And yet, if you have never felt the fear that previous generations had, that a mad man, or a mad regime, would one day acquire a nuclear weapon, you are about to. A dictatorship that held on to power three years ago by butchering and raping its citizenry is rapidly approaching the point where it will have the capability to build a bomb. According to the latest United Nations inspection, Iran has produced enough 20 per cent-enriched uranium in a single year to fuel its one nuclear research reactor for 15 years. Strange behaviour, you might think, for a regime that solemnly maintains it has no desire to build a nuclear weapon. Elsewhere, however, the regime's proxies are less concerned with keeping up appearances. In Lebanon the flags of Hezbollah are decorated with the symbol of a mushroom cloud; while the theocracy's more zealous newspapers have already begun to gloat over the potential a nuclear Iran would have to bully its Arab neighbours.

It is difficult to pinpoint exactly when lots of people in the West became comfortable with the prospect of an Iranian bomb. On the political left, it might even be accurate to say there is a greater clamber to condemn the prospect of the West disarming Iran than there is to argue against the theocracy being allowed to build a nuclear bomb.

Those weighing up the potential of a nuclear Iran in the hackneyed language of mutually assured destruction (MAD), however, or viewing developments only in terms of "Western hypocrisy", would do well to remember just how close we came to nuclear annihilation during the so-called "balance of terror" that governed the previous century. To those who believe that nuclear war today is unlikely, I feel compelled to point out that this is not, in any sense, enough. Any one of the following "incidents" should have rid us of the glib notion, based on feeble evidence, that the potential for worldwide nuclear war is confined to the realms of science fiction:

• During a meeting with Robert McNamara to mark the 30th anniversary of the Cuban missile crisis, Fidel Castro told the former United States Secretary of Defence that "of course" he was aware that the Soviet missiles situated in Cuba were nuclear-armed. "That's precisely why I urged Khrushchev to launch them," remarked Castro. Asked what he thought the consequences for Cuba would have been had Khrushchev heeded his advice, Castro said the island would have been "totally destroyed in the exchange", and added that McNamara would have "done the same" were he in the Cuban President's position.
• On 26 September 1983, Stanislav Petrov, the officer in charge of monitoring the Soviet Union's satellites over the US, intercepted a message indicating the launch of Minuteman intercontinental ballistic missiles from American bases. Soviet Premier Yuri Andropov believed at the time that the US was preparing an all-out first strike nuclear attack, and in anticipation had implemented a "launch at warning" order, which meant Soviet retaliation no longer required the usual confirmation of an enemy attack. Upon receiving the system alert, Petrov hesitated, and after five long minutes decided that the launch reports must be false. Petrov later told journalists his decision that the US had not started an all-out nuclear war was based partly on a guess.
• In 1979, British and American computer systems malfunctioned, and indicated that the Soviets had launched a massive nuclear attack. Fighter jets across the West were scrambled and emergency preparations for retaliation were made. Six minutes later the all-clear was sounded. The error occurred after a junior Canadian military officer put a tape simulating a Soviet attack into the wrong computer.

It hardly needs pointing out that the West has a huge stockpile of nuclear weapons. It is also quite true that one cannot preach non-proliferation, nor expect it, while simultaneously building up one's own lethal nuclear arsenal. That being said, I have not heard any plausible explanation as to why an Iranian bomb would increase the likelihood of the West getting rid of its nuclear weapons. Considering the fact that a nuclear-armed Iran would have broken every undertaking it has ever made to the European Union, to the International Atomic Energy Agency and to the United Nations, a more probable outcome is that a further nail would be driven into the coffin of non-proliferation, potentially consigning the cause, along with the League of Nations, to the history books. This would not simply be bad for Israel, as some on the more extreme fringes might wish, but would be an unimaginable disaster for all of us, including millions more who have not yet been born.

Those nostalgic for the old "balance of power", or practiced in a toy-town "anti-imperialism" that trumps a consideration for the lives of actual human beings, ought to at least have an idea of the potential consequences of what it is they are so blasé about.

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