I strongly disagree with those who say the after-effects of the invasion should not be focused on now. Remember Iran? The US forcibly installed the western-friendly Shah, which led to popular uprisings/support of the Ayatollahs/increased radicalism and mistrust of the west throughout the ME.
Now we've forcibly installed a western-friendly government into Iraq, with a set of binding orders/mandates that limit the government's ability to freely set policy. While many of the mandates are necessary, the perception is that the government is a puppet, set up by an outsider. History suggests this percieved excessive outside influence is a major cause of radicalism.
I don't have all the answers for what will work in Iraq given where we are. But what Bremer et. al. have done up to now seems to ignore history.