Should the US leave Iraq?

I was asked today whether I think the US should leave Iraq and I realized I have not written about this issue for a while.

The answer is no, I don't think that the US should (or can) leave right now, that would probably lead to a real civil war. So the question is instead: what can be done about the present situation, and how we can end up in a situation where the Iraqis can govern and rule their own country without any foreign involvement?

Clearly a new policy in Iraq is needed. The most interesting initiative I have heard about lately comes from a group of people at the Brookings Institution. The group suggests a new, more integrated approach with concrete proposals within most policy areas (economics, infrastructure, military operations, organization, etc). Read more about their work and policy proposals here, and I would happily receive advice about other promising ideas.