Victor Davis Hanson pretty much sums things up:

Rather than blaming Donald Rumsfeld or George Tenet, the principled position of the “my three-week perfect war was loused-up by your five-year occupation” critic would have been an honest admission that they underestimated the potential of Iraqi insurgency, and that even its defeat was simply not worth the commensurate American costs….

Instead, what we have now are dozens of loud, pick-and-choose opportunists who were for the war, then soured on it, then came back some during the purple-finger elections, then got angrier during the February 2006 insurgency, then damned the surge, then grew quiet during the Petraeus success — always, in retrospect, citing a particular past phase of their ongoing metamorphoses when it now seems to best amen the current status in Iraq.

Sadly, most have no ethical bearings, and wrongly judged our presence in Iraq in terms of wishing to identify with a winner and to distance themselves from a perceived loser. The irony, of course, is that in the months to come many abroad will begin to respect our support for Iraqi democracy only for the self-interested reasons that it proved successful rather than principled.