How much would it matter if Iran had the bomb? Merely to pose this question, within the Bush administration, would almost be treason. European countries, for their part, consider it indiscreet to raise it - better to say that a nuclear-armed Iran should be avoided if at all possible. Yet the question of how dangerous a development it would be is crucial.
Dangerous enough to justify a war, which is what the United States, and sometimes Israel, seem to think? Dangerous enough for major sanctions, in addition to the American ones already in place, which both those countries certainly would argue? Or merely regrettable and worrying, but not worth making worse by either economic or military action, which is probably the underlying position of the three European nations trying to mediate between the United States and Iran over the Iranian nuclear programme?
These differences, usually hidden by the efforts of the US and the EU to "stay on the same page" on Iran, are likely to be wrenched into the open in the next few weeks if the Iranians resume fuel-enrichment activities, as they have said they will. First at the International Atomic Energy Authority, and then, if the issue goes there, at the UN security council, the Americans and the Europeans will be trying not only to overcome the indifference or hostility of many non-western states but to reconcile their own deeply divergent views.
It would still, of course, be a bad thing. Proliferation by its nature increases the chances of the use of nuclear weapons, multiplying the bad possibilities of their use by states or by terrorists. But, if it were to attack Iran, the United States would face a world united in its opposition to what the leading power was doing. Israel's chances of peace, if it took part, would be terribly damaged. Iran's possible evolution into a freer society, evident in the social, demographic and cultural developments that are already leaving the mullahs trailing behind, would be disrupted. In any sane ordering of calamity, an Iranian bomb or "near-bomb" must surely rank well below the disaster of a major conflict between the United States and Iran.
http://www.guardian.co.uk/Columnists/Column/0,5673,1483080,00.html