I think you are talking about former LtCol Dave Grossman's book On Killing. About the need to train people to kill. Very interesting stats re: soldiers who didn't fire their weapon in combat, guys who supported their buddies firing rate but wouldn't fire themselves. I believe he even had a rifled musket from Gettysburg that had 9 charges in it that obviously were never fired, but the soldier still did the drill.
Sounds like it. Some people need training to kill as a duty, some people are better off not being trained to kill.
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