My education also drilled into me the distinction between what one can do and what one may do. I can just hear my main lesson teacher now: "Can an illegal immigrant vote? Perhaps, but they may not, and certainly they should not."
More of teaching like this in school could go a long way, but once people reach adulthood I don't think this would cut it. I think a more military training approach might be needed where you tear this part of the person's psyche down and rebuild it properly from the ground up.
