Military leaders know a secret: The vast majority of people are overwhelmingly reluctant to take a human life.
During World War II, U.S. Army Brigadier General S.L.A. Marshall asked average soldiers how they conducted themselves in battle. Before that, it had always been assumed that the average soldier would kill in combat simply because his country and his leaders had told him to do so, and because it might be essential to defend his own life and the lives of his friends. Marshall's singularly unexpected discovery was that, of every hundred men along the line of fire during the combat period, an average of only 15 to 20 "would take any part with their weapons." This was consistently true, "whether the action was spread over a day, or two days, or three."