You're being short-sighted here, Dave. As much as I'd really, really like to curl up in the warm cocoon of a missile defense shield and tell the rest of the world to piss up a rope, we can't do it any more.
If we drop the ball on Iraq what's going to fill the void? The Iranian theocracy? Our best buddies the Saudi's? We've got to do this the right way, rebuild the country into some semblance of progressiveness and stability, and our presence in Iraq as big stick for the rest of the Arab world.
We've now got ongoing operations happening next to the 4 main state perpetrators of terrorism; Iran, Saudi Arabia, Syria, and (in Afghanistan) Pakistan. It's not a coincidence that we're in this position. GW's going to let the heat die down, win the next election, and in the coming 4 years the screws are going to be turned on these worthless sandholes.
Mark my words.