McCain is questioning Obama’s judgment for opposing the Surge, even in retrospect. McCain is claiming that the Surge alone is the cause for the dramatic decrease of violence in Baghdad. But a map of the demographic shift in the city over about a year and a half shows that the real reason is that the Sunni and Shia have segregated themselves into separate warrens. Where there is less contact, there is less friction. Also, the genesis of the “Anbar Awakening” movement actually preceded the Surge and was a backlash to al-Qaeda’s sheer brutality against civilians. No doubt the addition of five US brigades helped to quiet things down, but it’s not the only factor. In real life things are gray, not black and white.