What did cause the turnaround since 2006? Three competing explanations have popped up. Some have claimed that covert operations, involving the use of top-secret technical devices, are what drove the insurgency’s leaders from Iraq. Others attribute the turnaround to Bush’s decision in January 2007 to add 30,000 more troops. And still others suggest that it is the brilliance of General Petraeus, who took command in Iraq in February of 2007, that we have to thank for the improvements.

There is some truth to each of the three explanations. But all fall wide of the mark. The foremost reason for the turnaround is that the Sunni population switched from attacking American (and Iraqi Army) soldiers to aligning with them against al-Qaeda. What prompted that switch was the behavior of the American soldiers contrasted with that of the al-Qaeda fighters.

Beginning in 2003, the Sunnis had welcomed or at least accepted al-Qaeda in Iraq (AQI). The rate of infiltration from Syria, primarily into western Anbar Province, was about 100 to 200 a month in 2003 through late 2005. This small minority proselytized among the dozens of local resistance cells, many of whom were initially Baathist-led. AQI recruited the weak-minded and especially the criminal elements. Waving the banner of jihad, AQI killed Americans and Shiites. They then began to expand the range of their targets, going after all foreigners associated with the fledgling Iraqi government (truck drivers from Jordan, aid workers, etc.), then Sunnis who worked for the government, then Sunnis suspected of betraying al-Qaeda members, then Sunnis who objected, and so on.

In 2003-2004, the Americans were the robo-cop outsiders, tough in battle but not understanding of the environment. Battles like Fallujah alienated the Sunni population. Americans won every battle, but al-Qaeda always returned after the Americans left.

By 2005, AQI had solidified its hold over the Sunnis, based on terror rather than religious or tribal solidarity. At the same time, the Americans were learning to act with restraint, while still prevailing in every test of strength. The U.S. military also finally convinced the State Department to allow colonels and generals to meet with the resistance. The American message to the Sunni resistance leaders was simple: Why are you fighting us? We bring you contracts and protection. We act as a buffer and an ombudsman with the Baghdad government. You Sunnis have it backwards. You roll over for the AQI who are killing you, and you ignore or abet attacks against us, when we are looking out for your best interests. Well, one day we will be gone and you will have al-Qaeda as your undisputed masters. Drive out AQI while we are still here to help.

That message eventually got through. In late 2005, a dozen prominent sheiks in the Ramadi area tried to organize against AQI. Their movement was blasted apart by suicide murderers and assassins. The basic operational approach of the Marine Expeditionary Force in Anbar was to deploy in company outposts in the villages and cities and daily conduct hundreds of foot patrols. This was called a “clear and hold” strategy. But Al-Qaeda hadn’t been cleared; its covert cells controlled the population in Anbar.