distancing
psychological, physical and social distancing is what is needed in order to commit violence.
a good read is "On Killing" http://www.google.com/search?client=...UTF-8&oe=UTF-8

its much easier to be "rude" with anonymity, encapsulated in 2800lbs of metal and glass, with +100hp and ease of use.
things like nintendo warfare, neutralizing a target, overtaking an objective, "passing a car", etc... <-- all forms of "distancing"