Three weeks ago, Binyamin Netanyahu flew to Washington to insist once again that Israel would not accept a nuclear-armed Iran; and neither, he intimated, should the United States. Mitt Romney, to gain a few votes in Florida, promised that under any administration of his, the US would deal with Iran once and for all. Iran, as well as the American electorate, is listening. If you want to convince the mullahs to accelerate a drive towards the bomb come November, that’s the way to do it.

Precedent is often cited to argue for military strikes against Iran: namely, Israel’s destruction of the Iraqi nuclear reactor at Osirak in 1981. But Osirak is little more than a lesson in the dangerous misuse of precedent. The Iraqi reactor was a single above-ground installation in a country far closer to Israel. And, as Norman Dombey has pointed out, it was a light-water reactor, ill-suited to producing plutonium for a nuclear bomb. The serious Iraqi weapons programme followed the Osirak strike – and was very probably prompted by it – before being dismantled after the first Gulf War.

Iran learned from Osirak too. A US official told me that Iran took the decision to ‘decentralise’ its programme because of it. Iran’s nuclear facilities are dispersed throughout a country far larger than Iraq, buried deep underground and encased in the hardest concrete ever developed. Submarines launching missiles from the Suez Canal would require Egyptian consent, unlikely to be forthcoming post-Mubarak, while the Azerbaijani government recently denied (angrily) that it would allow Israel use of its airbases, either for take off or refuelling. Only the US could effectively strike the facilities, but it won’t – and it doesn't want Israel to either.

Even if a strike could succeed, would it be worth it? The most likely immediate result would be a determined Iranian drive to develop a bomb. Iran could use it as an excuse to leave the NPT, and the nation’s demagogues could tell their oppressed people, most of whom understandably loathe them, that Obama’s détente was never sincere and it’s time to cast off internal divisions and unite in the face of the enemy. For this reason many hardliners in Iran welcome further confrontation with the West.

Then there is the question of the wider fallout. Iran has promised to respond in kind to any attack: it would almost certainly launch its Shahab-3 ballistic missiles at Israel and encourage Hamas and Hizbullah to create more trouble for Tel Aviv. But what the White House really fears are attacks on American troops in the Gulf and CIS Republics, and the further destabilisation of Afghanistan and Iraq – all for a strike that’s unlikely to work anyway. A former head of Mossad, Efraim Helavy, said an Israeli attack would prompt a wave of ‘revulsion’ against Tel Aviv likely to last for years. His successor, Meir Dagan, responsible for the policy of assassinating Iranian nuclear scientists, and not a man to be accused of being ‘soft’ on Iran, described the idea as ‘stupid’. What may seem the only ‘solution’ left is the one means of ensuring the crisis escalates to unmanageable levels.