The very worst US foreign policy disaster of our lifetime is the Iraq invasion and occupation. John McCain and Hillary Clinton supported it. Barack Obama didn't.
Yet... now what? Of course it's complicated. We - we, Americans, that is - are all implicated in the Iraq War. It doesn't matter if you didn't vote for Bush and never supported the war. Our system is quasi-democratic, which at least means that we give our tacit consent to domestic regimes we dislike or haven't personally chosen. So, we can't simply take a cavalier attitude towards either withdrawal of American troops or some idiotic "100 years" statement. We're responsible for a solution that saves Iraqi and American lives. The surge is a smokescreen, a cowardly policy option intended to buy time for the current administration. The real policy will be made by the next president.
But... do you trust someone who fully supports the war and suggests more of the same, someone who maybe or maybe not supports it, or someone has always been against it to make the right choices about what will in any case be an exceedingly difficult foreign policy mess to sort out?