Iraq, too, was decisive, though not in the way we intended. We no more chose it to be the central campaign in the crushing of al-Qaeda than Eisenhower chose the Battle of the Bulge as the locus for the final destruction of the German war machine.

Al-Qaeda, uninvited, came out to fight us in Iraq, and it was not just defeated but humiliated. The local population — Arab, Muslim, Sunni, under the supposed heel of the invader — joined the infidel and rose up against the jihadi in its midst. It was a singular defeat from which al-Qaeda never recovered.

True, in both wars there was much trial, error and tragic loss. In Afghanistan, too much emphasis on nation-building. In Iraq, the bloody middle years before we found our general and our strategy. But cannot the same be said of, for example, the Civil War, the terrible years before Lincoln found his general? Or the Pacific campaign of World War II, with its myriad miscalculations, its often questionable island-hopping, that cost infinitely more American lives?…

9/11 was our Pearl Harbor. This time, however, the enemy had no home address. No Tokyo. Which is why today’s war could not be wrapped up in a mere four years. It was unconventional war by an unconventional enemy embedded within a worldwide religious community. Yet in a decade, we largely disarmed and defeated it, and developed the means to continue to pursue its remnants at rapidly decreasing cost. That is a historic achievement.