After the U.S. military-transformed into a lean, lethal, computerized force-faltered in Iraq after 2003, a robust insurgency arose. Counterinsurgency became a social form of war-indeed, the U.S. Army calls it 'armed social work' -in which the local population was the center of gravity and public opinion at home the critical vulnerability.War 2.0 traces the contrasting ways in which insurgents and counterinsurgents have adapted irregular conflict to novel ...