He has a great blog posting called Exit Strategies about a discussion he recently had with a highly experienced mercenary with significant experience in many global conflicts.
It’s worth a read. In short, the fellow in question said that security is deteriorating rapidly, that the coalition was collapsing, that history always sides with the “liberated” guerillas and that the best exit plan was to let Saddam go back to running the country. Yes, you read that right. After all, he was a cruel bastard but he kept the country from collapsing. All disparate, multi-factional, multi-language regions are generally contained only by threat of force (see Indonesia for another example.)
In this post, Barlow offers up his own plan, some of which I actually don’t understand.
But the post is a good read.