Like it or not, the US is the only super power and a target for all of the nuts and animals in the world.
Even John Effin Kerry wouldn't pull out of Iraq - we'd leave a power vacuum and the back door to our weakness (energy) wide open.
The US needs a base in the middle east and Iraq is it.
Remember, after defeating the Germans and Japanese in WWII, and then saving the South Koreans, it took about 30 years before they became major economic and social powers in their own right. That thought, that Iraq could become a democracy and major economic and social power must scare the hell out of all of the little regimes surrounding Iraq.