Iran and Realpolitik
There is now no doubt that something needs to be done about Iran. Despite the Iranian protestations that thier nuclear program is for civilian purposes only, everyone accepts that it is really a "clandestine nuclear program" (thats from the french foreign minister).

So what to do about it is the only real question now. Well, the options are....

1) a "limited" or "precision" strike with smart weapons.

2) Regime change

3) Use of Nuclear weapons

4) Sanctions and Diplomacy

5) use of a proxy power to attack Iran.

What would you do?

I know what I would do. Consider this, Limited strikes on countries that can hit back don't stay limited for long. Regime change is probably beyond our capabilities (just look at Iraq). Using Nuclear weapons on  nuclear facilities would allow Iran to hit back. Using Nuclear weapons on Iran proper would be morally wrong and the USA's former allies would be horrified.
So the options left are Sanctions and a proxy power. That is just what the Administration will do. They will push sanctions on to Iran in the hope that Iran will refrain from building a Nuke, or at the 2009 elections moderates will win out. When Iran is very close they will mutter the words and the satellite images to Israel. There will be a war. Thousands will die as Iranian missiles can hit Israel easily now.
Thats what the US is doing, and its another reason to get out Iraq by the time the Iranians nearly have a bomb.