First of all, as I've repeated before, I don't know why we should draw any consolation from the fact that 90% of the Iranian people will be really sad for us if their mullah crazies detonate a nuke in Charleston harbor. Lighting candles just won't cut it for me.
Second, I question if this conventional wisdom is even accurate (see here and here for a couple examples from earlier). Let me quote one of my posts:
Opponents of destroying the Iranian regime say any military action against the mullahs will only rally the people to the side of the mullahs.
Why do we accept this belief? Has our Left rallied to President Bush in the face of 9-11? Why must people in Iran automatically support a theocratic regime that kills children for holding hands when some Americans can't support a President who they think is a fascist theocrat in their wild rantings?
Given that opponents of military action to support the overthrow of the mullah regime in Iran oppose any military action anywhere under this president, why should we accept as a given their assertion that Iranians will rally against a foreign threat? The goal of the Left is to stop military action so their analysis is hardly objective. Indeed, it is hardly uncommon for dissidents in one state to look to foreign allies that are enemies of the government to win at home.
Edward Luttwak (via Real Clear Politics) questions this automatic assumption of loyalty, too. He notes, rightly, that Iran is an empire of various peoples ruled by Persians:
To the extent that the different nationalities each have their own identities and oppose the essentially Persian regime, they are likely to applaud external attacks on the nuclear installations rather than rally to the defense of their rulers.
After detailing the ethnic and religious groups of Iran, Luttwak concludes:
So, all in all, at least half the population is unlikely to be motivated by feelings of solidarity with their rulers. Only among the Persians are many likely to react to an attack as the axiom prescribes; others might welcome the humiliation of their oppressors. The bombing of Iran's nuclear installations may still be a bad idea for other reasons, but not because it would strengthen the hold of its rulers. One may hope that Iran's rulers are not misled by their own propaganda and will therefore accept a diplomatic solution rather than gamble all on an irrelevant axiom.
Personally, I think the Iranians aren't so much counting on a rallying effect if we attack them as they are assuming we wouldn't dare attack them.
But the basic point is that whatever we decide is the best means to prevent Iran from going nuclear (and good God, we have decided that, haven't we?), we should not rule out any option because we think the Iranian people might rally around the flag. Both because their opinion of us matters not one bit if we are looking at a new ground zero in our country and because it is a questionable assumption on which to base our safety.
And Iranian regime opponents may very well view a military attack not as a crisis, but an opportunity.