Despite President Bush's claims that Iran is pursuing nuclear weapons that could trigger "World War III," experts in and out of government say there's no conclusive evidence that Tehran has an active nuclear-weapons program.
And even if Iran did acquire a nuclear weapons capability at some point in the future, they would be effectively deterred from using it by the threat of total annihilation - the very same logic of deterrence which we relied upon to prevent nuclear war with the Soviet Union (remember them? PAF enjoys a moment of nostalgia).
Ahmadinejad's alleged threats against Israel have been similarly exaggerated and distorted, and in any case his office is not equivalent to the American Presidency and he is not in control of Iranian Foreign Policy.
There is no reason to believe that Iran poses a grave threat to the existence of Israel or to the security of the US. But a nuclear-armed Iran would be harder for Uncle Sam to push around insofar as they too would possess some deterrent capability. So PAF thinks the reason for the push to attack Iran now is to forestall a situation in which Iran might have some ability to deter or limit US military expansionism in their neighborhood. US imperial domination of the region may be at stake, but US or Israeli survival and security is not.