At the time of the U.S. invasion of Iraq in March 2003, counterinsurgency theory was about as popular in American military circles as tank warfare is today. An early study by the chief war planner for the 101st Airborne Division during its first deployment to Iraq reported “a collective cognitive dissonance on the part of the U.S. Army to recognize a war of rebellion, a people’s war, even when they were fighting it.” There was a reason for this. Eager to forget the most painful experience in its history, the army had all but banished counterinsurgency from the lexicon of American military affairs after Vietnam. As a result, the army relied on a flawed strategy in Iraq for a period that lasted, according to author Thomas Ricks, at least “twenty months or more.”

