The level of non-combatant casualties in modern Western warfare is determined in large part by the way in which policymakers apportion risk between soldiers and civilians. In the U.S. counterinsurgency in Iraq, a “kinetic” strategy and a muscular doctrine of force protection have lowered the threshold for the use of violence and, in many cases, transferred risk from soldiers to civilians. Particularly in areas deemed hostile, aggressive tactics make up for a shortage of soldiers on the ground and direct violence toward non-combatants. This is not the fog of war: even unintended civilian casualties flow predictably from policy choices. Perceptions of risk increasingly govern U.S. interpretations of its humanitarian obligations under international law, threatening to dilute the doctrine of proportionality and reverse the customary and legal relationship between combatants and non-combatants. Only late in the war has the U.S. administration recalibrated risks and launched a more orthodox counterinsurgency strategy.