In Washington and in the world at large, fears are growing that the US may mount a pre-emptive military attack on Iran.

President George W. Bush recently described the dispute over Iran’s nuclear programme in near-apocalyptic terms, warning America’s partners to prevent Tehran from obtaining the bomb if they were “interested in avoiding world war three”. Vice-president Dick Cheney declared, in an echo of his prewar rhetoric on Iraq: “We will not allow Iran to have a nuclear weapon.”