Discussion Points: Should Superheroes Kill?

There's a trend that seems to come up now and again in comic books regarding superheroes and their tactics.  People keep asking "why doesn't Batman just kill the Joker?"  "Why doesn't Captain America just kill <insert name of Nazi who keeps reappearing here>?"  "Why didn't Power Pack ever kill off Crazy Legs?"

Four white kids killing a black(ish) guy?  He probably had it coming.

Well, let's talk about this, and I'll give my opinion on it.