Let's not kid ourselves. There's something satisfying about making a kill at a distance, no matter the target.
Not trying to psychoanalyze anything here, but there's a good feeling when you down a man. Even in everyday terms, when you fight, or box, when that man opposite you crumples due to a well-placed blow, it doesn't matter your political affiliations or philosophy, it feels good! It is actually quite addictive, and that's why you get a lot of BG doing it over and over. (It's just being legal and civil in a civilized society that it makes it not a good idea to partake.)