Maybe. Shooters usually have you mindlessly killing "the enemy" and they're usually inhuman. If they are human, they're dehumanized, "those guys are criminals, kill 'em," "those guys are [url=http://www.wikipedia.org/wiki/Godwin%27s_law]-godwinslaw!-[/url], kill 'em" you just mindlessly shoot people without considering them as humans. Do that enough and you may feel less qualms about actually doing it, idk.