“In recent days, many veterans have made the point that fighters cannot do their jobs without creating psychological distance from the enemy. One reason that the soldiers seemed as if they were playing a video game is that, in a morbid but necessary sense, they were.

Military training is fundamentally an exercise in overcoming a fear of killing another human, said Lt. Col. Dave Grossman, author of the book “On Killing: The Psychological Cost of Learning to Kill in War and Society,” who is a former Army Ranger. ”

http://www.nytimes.com/2010/04/08/world/08psych.html?partner=rss&emc=rss