Hopefully, this sergeant will thaw out his attitude before the next time he asks for a favor from someone he has been treating like absolute garbage. It's really not that hard to be nice to someone—or at least decent—and deciding to hate them for a petty tribalist reason, like being a fan of a rival sports team or a member of another branch of the military, is downright insane. It's the kind of thing that works ok as a low-budget melodrama TV show plot or between two kids on the playground—but…