"On Killing" by retired Lt. Col. Dave Grossman examines the psychology of killing, and offers extensive research to show how men and women react when faced with that decision.
Much of his findings stem from the research of Brig. Gen. SLA Marshall, an Army historian whose book "The Soldiers Load and The Mobility of a Nation" has been on the Commandant's list at varying points over time.
Grossman found that most people have a distinct aversion to killing. Not only do you have to properly train soldiers to kill, Gorssman writes, but you also have to be sure that they are equipped to handle the psychological consequences that killing can take on the psyche.
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