Similarly, when the "Anbar Awakening" began in western Iraq, a movement in which Sunni insurgents allied with U.S. soldiers to beat back their common enemy of al-Qaeda jihadists, Petraeus stepped up the operation by paying the converted insurgents with money from his commander's discretionary fund—a move of borderline legality—again, without telling anyone in Washington. Recruitment soared. The move on Sadr City and the recruitment of Sunni insurgents turned the tide in the war.
For any of these measures to have worked, though, President George W. Bush had to approve the new counterinsurgency strategy as official U.S. policy—and he had to send more troops to Iraq.
The top generals in the Joint Chiefs of Staff opposed both measures. In the months before he took over as top commander, Petraeus coordinated the behind-the-scenes maneuvers to overwhelm their opposition.
He cultivated a back channel of influence to the White House through Bush's top adviser on Iraq, Meghan O'Sullivan, who was coming to agree with Petraeus' views. Petraeus and a few others made sure that an analytical study, favoring a surge, was circulated through the White House, the Pentagon, and headquarters in Iraq at just the right moment. Bush announced the new strategy, the surge, and Petraeus' nomination as new commander all at the end of 2006—around the same time the counterinsurgency field manual was published.
Yet as often happens with revolutions, the new doctrine later hardened into dogma.
Petraeus tried the same techniques—imposed the same "big ideas"—when he took over command in Afghanistan, but they didn't work. It was a different environment, with different politics, different culture. The conditions in Iraq had been ripe for counterinsurgency; the conditions in Afghanistan bore no fruit.
The lesson is that creative ideas and shrewd strategists don't guarantee success. The terrain limits the possibilities; the enemy has a voice.
Fred Kaplan is the author of "THE INSURGENTS: David Petraeus and the Plot to Change the American Way of War." Kaplan writes the "War Stories" column in Slate and has also written many articles on politics and culture in The New York Times, The Washington Post, New York magazine, The Atlantic, Foreign Policy, and many other publications. A former Pulitzer Prize-winning reporter for The Boston Globe, he is also the author of 1959: The Year Everything Changed, Daydream Believers: How a Few Grand Ideas Wrecked American Power, and The Wizards of Armageddon.