Mako's right. From what I've been hearing, the Iranian general public don't hate the US as much as the Theocracy there would have us believe. Remember, the images we see of the Iranian people foaming at the mouth about the 'evil US' is carefully vetted by the state media machine to make it seem like there's 100% nationalist fervour. I think it would be a big mistake to blur the line between the people and the theocratic dicks who oppress them. These aren't North Koreans with a personality cult. The Ayatollahs have had a bit of a crisis in trying to stem (and failing pretty consistently) the Iranian youth's taste for Western trends, clothing, technology, freedom of speech, etc. Give the Ayatollahs and the government a bloody nose (I'm talking the kind you get when you try to catch a brick with your face!), you'll start seeing popular resistance to theocratic rule as we did in the Arab Spring and that's half the fighting done for you there. You go all shock and awe in Iran and civilians die, it'll end horribly and you won't be facing just Iran in the ME. This goes especially for Israel. They have no friends in the region and if they act unilaterally, a lot of organisations (state sponsored and others) will want a piece of the revenge pie. It'll be bloody for years. And remember, it's further away than the site in Operation Opera, so the chance of success is lower.
Besides, if Iran is dumb (and it would be an act of EPIC STUPIDITY!!) enough to attack can of nuclear powered kick ass like a USN carrier in what the United Nations Convention on the Law of the Sea and the rest of the world recognises as a free transit zone for shipping, not only will they get their arses comprehensively handed to them by superior US firepower, they'll attract a flood of condemnation and sanctions and it'll probably deliver a free kick to the US to take out that damned nuclear reactor site...