But, "we know that, like any boxer, they can come back up off that canvas and lend a big, right-hand punch." That from an interview General Petraeus gave to Foreign Policy, which can be found here. I think the key point is made here:
FP: So having to ally with past enemies is not a failure but a success? DP: Not all of them were our enemies. Some were what we call fence-sitters; some were oppressed and some probably were shooting at us, but you don't kill your way out of this kind of thing. You can't kill or capture everybody in an insurgency. What you have to figure out are the irreconcilables, and ideally you want these numbers as small as possible because they have to be killed, captured, or run off.
Petraeus talks about the dramatic decline in violence, which is really the only metric that can be used to gauge the effectiveness of Coalition efforts. There's little U.S. forces can do to spur political reconciliation at the national level, they can only create the conditions that will allow for such reconciliation. And they have done so. Now that part is up to the Iraqis themselves. But turning the people of Anbar against al Qaeda--that is clearly a success. It's like asking if turning Italy against the Axis was a failure or a success. The result speaks for itself. Anytime you turn an enemy into an ally, you're doing something right.