There was a very astute comment left in response to my post on evolution and psychopaths:
Normal people (however you define that term) can be desensitized to the suffering of others. Soldiers fighting in a war – those who don’t become shellshocked – become insensitive to killing and wounding. Indeed, people with ordinary lives sometimes have to “harden their hearts” just to do their jobs.
I think one of the more uplifting facts of human nature is that it’s very hard for us to “harden our hearts”. Consider the behavior of soldiers during war. On the battlefield, men are explicitly encouraged to kill each other; the crime of murder is turned into an act of heroism. And yet, even in such violent situations, soldiers often struggle to get past their moral instincts. During World War II, for example, U.S. Army Brigadier General S.L.A. Marshall undertook a survey of thousands of American troops right after they’d been in combat. His shocking conclusion was that less than 20 percent of soldiers actually shot at the enemy, even when under attack. “It is fear of killing,” Marshall wrote, “rather than fear of being killed, that is the most common cause of battle failure in the individual.” When soldiers were forced to confront the possibility of directly harming another human being, they were literally incapacitated by their emotions. “At the most vital point of battle,” Marshall wrote, “the soldier becomes a conscientious objector.”
After these findings were published in 1947, the U.S. Army realized it had a serious problem. It immediately began revamping its training regimen in order to increase the “ratio of fire”. New recruits began endlessly rehearsing “the kill,” firing at anatomically correct targets that dropped backwards after being hit. As Lieutenant Colonel Dave Grossmann noted in his book On Killing, “What is being taught in this environment is the ability to shoot reflexively and instantly…Soldiers are de-sensitized to the act of killing, until it becomes an automatic response.” These new training techniques had dramatic results. When Marshall was sent to the Korean War, he discovered that 55 percent of infantrymen were now firing their weapons. In Vietnam, the ratio of fire was nearly 90 percent. The Army had managed to turn the most personal of moral situations into an impersonal reflex. Soldiers no longer felt a surge of negative emotion when they fired a weapon. They had been turned, wrote Grossmann, into “killing machines”.
Sometimes I wonder if this increased “ratio of fire” in modern war is a one of the causes for the dramatic increase in PTSD among veterans. You can train people to kill, but can you really erase the emotional stress that is automatically generated when we hurt somebody else? I don’t know.