So did the "surge" "work"?
The troop escalation in and of itself was probably not that consequential. That the troops were used in new ways by Gen. Petraeus was more important. But their main effect was ironic. They calmed Baghdad down by accidentally turning it into a Shiite city, as Shiite as Isfahan or Tehran, and thus a terrain on which the Sunni Arab guerrilla movement could not hope to fight effectively.
It is Obama who has the better argument in this debate, not Senator McCain, who knows almost nothing about Iraq and Iraqis, and overestimates what can be expected of 30,000 US troops in an enormous, complex country.
But the problem for McCain is that it does not matter very much for policy who is right in this debate. Security in Iraq is demonstrably improved, for whatever reason, and the Iraqis want the US out. If things are better, what is the rationale for keeping US troops in Iraq?
More at Informed Comment.