I think this is a great analysis:
http://fallbackbelmont.blogspot.com/2006/01/grappling-with-ayatollahs.html
Grappling with the ayatollahs
John Keegan lays out what sees are the West’s options with respect to Iran:
http://www.portal.telegraph.co.uk/opinion/main.jhtml?xml=/opinion/2006/01/12/do1202.xml&sSheet=/opinion/2006/01/12/ixopinion.html
[i]The pressing question is, indeed, what is to be done when a report to the Security Council fails to bring Iran to desist from nuclear enrichment? ... It is much more doubtful whether sanctions would make Iran change its policy. ...
America and the EU3 must therefore consider other, harsher methods to restrain Iran. The fact that the United States at present deploys a large army in Iraq is a factor that must give the ayatollahs pause. To stage a second war in the Middle East would not be a desirable initiative at present for America and would certainly be highly unpopular at home and among its allies. Moreover, Iran, as the possessor of the second largest oil reserves in the world and occupier of a strategic position athwart the sea routes delivering oil to most of the consuming world, has its own means of retaliation ready to hand.
Nevertheless, the West cannot simply let things drift. Military action by whatever agency cannot be written out, but will be a last resort. ... For if the West is considering military action, so are the ayatollahs. They are the sponsors of much of the insurgency in Iraq and suppliers of the insurgents' weapons. They also have intimate links with most of the world's worst terrorist organisations, including al-Qa'eda and Hezbollah. ... Moreover, while Iran has its own armoury of medium-range missiles suitable for nuclear delivery, the ayatollahs are also known to favour the placing of nuclear warheads in target cities by terrorists travelling by car or public transport. This is a bad and worrying time in world affairs.[/i]
Commentary
The most interesting thing about the structure of the standoff between the West and Iran is that what chiefly prevents a regime change in Teheran is not the want of means, but the want of will. The ayatollah’s fundamental defense lies in the well-founded belief that the United States has expended too much political capital in deposing Saddam to undertake another regime change operation in Teheran. Safety for the ayatollahs does not consist in the assurance that there aren’t enough US ground, air and naval units to smash their regime, but in the calculation that no American President would chance it after three years of political pillorying for OIF.
That means that the ayatollahs are safe for so long as nothing occurs to prevent a sudden stiffening in political will in the West. John Keegan is correct when he says that the ayatollahs have military options. What he does not pursue is what should happen if the ayatollahs actually use them. The Iranian regime operates under the unstated, but nevertheless real constraint that in confronting the West it must take care not to go too far. If Iran were to simply quietly acquire nuclear weapons it would be doubtful whether the United States leadership could muster enough political steam to crush the ayatollahs. However, if the ayatollahs were rash or enraged enough to actually strike the West the equation could change overnight.
Both the regime in Teheran and Washington are like Olympic wrestlers grappling within a narrowly bounded mat. The instant anyone should step or be forced outside the mat the buzzer will sound and a new and deadlier match will begin. Unfortunately the boundaries of the arena are invisible to both sides. How far can America push Iran? How far can Iran push America? Iran has the advantage of knowing that the US will stop short of overt military action against them – for the time being. But it has the disadvantage of not knowing how far it can let Al Qaeda and Hezbollah go without bringing down the spectators from the stands.
This makes the feint the deadliest weapon in the US arsenal. Sending air wings to exercise in Southwest Asia, for example, is something the Iranians will deeply resent. But should they respond – even if they could? It was said of Admiral John Jellicoe that he was the only person capable of losing the First World War in an afternoon, because as commander of the British Grand Fleet, he could throw away the foundational power of Britain in a single naval disaster.
It may equally be said that Iranian President Mahmoud Ahmadinejad alone can strip Iran of its invulnerability to military action in a single rash moment. In that sense he is not, as some pundits think, the worst possible leader Iran could have at the moment. On the contrary, this unstable, bellicose man is from another point of view the answer to all his enemy’s prayers.