There is always a moment during a raging battle when one side realizes that the field has been won, and the other side collapses in retreat and confusion. The curious thing about the Iraqi insurgency is that this moment has arrived, yet both the victors, in this case the Americans and the Iraqi government, and the losers, Al-Qaeda and the other jihadist groups, are reluctant to acknowledge it. But make no mistake, the battle has been turned and we are witnessing the beginning of a jihadist meltdown. Six months ago, many of the strategists behind the Sunni insurgency, faced with...