That surge architect Fred Kagan thinks the surge's failure to deliver results merely proves the need to take more time with the surge is unsurprising. The end of the article, however, is striking. Kagan, according to Time's Michael Duffy, "fears a significant increase in Iranian support for those fighting U.S. forces. Finally, he noted that the shaky government of Nouri al-Maliki could just implode."
While that might not end the cause of progress in Iraq, Kagan said, it could lead to something worse for those who believed a surge would lead to a stabilization of Iraq: a breakdown in political support for the war effort in Washington.
In other words, according to Kagan even the total collapse of the Iraqi government wouldn't, in his mind, demonstrate that the war had failed. Even under those circumstances he's going to stick to the stab in the back story that the only problem is the collapse of political support for the war here in DC.