That starts to sound at least vaguely like the exit strategy we pursued in Afghanistan, in somewhat different forms, both times we intervened: leave the militias in place, and hope they can work something out -- possibly with a "national government" in place whose sole practical power is to mediate between the factions (as in the more recent instance), but in any case, with a lasting peace ultimately dependant on the good will of all the parties. The first time around, we got the Taliban. It remains to be seen what will ultimately come of the second.
And, having griped about it, I must add again that something like this might be our least worst option -- given how badly our screwups have destroyed our credibility and even ability to achieve anything better. Let's hope for credible mediators; at this point, they're our last, best hope.
On which point, by the way, see Laura Rozen's speculation that interference with UN diplomat Lakhdar Brahimi's work trying to form a credible governing coalition may have been the hammer stroke by which Chalabi put the last nail in his own coffin -- her blog has been Chalabi central since the raid, if you have an interest in the story generally. And dealing with another, vaguely related mystery, the Times has a news story and an op-ed which offer different sets of clues to a different mystery -- why have the Saudis' concerted efforts to lower oil prices been such a failure?