There will not be any nation building in Iraq. The entire area is populated by nuthouse people and nuthouse religions. About 20 years ago Iran and Iraq were involved in a 10 year long war over nothing in which they killed off 50% of the male population of a generation. That's what is to be expected in the area.
What needs to be done is let them kill of each other, but establish the principle that if they leave their territory and mess with us, they'll get a bunker bomb on their heads. This war will be an act of genius if it inspires fear in the rest of the world so that a disapproving word of warning toward the world idiots will cause them to pee in their pants. If this direction is not pursued, it will all be for naught beyond another Bush strutting around thumping his chest for a few months. North Korea needs their missile sites destroyed next.