On a side note, wishing a bastard had been shot is not the same as "that bastard should have been shot" or "it would be great if people could carry guns so that guy would have been shot." I think it is possible to wish someone had gotten shot while believing that it may not be a great idea to allow guns on school campuses. Of course, that doesn't seem to be the case here, but you also seem to be presenting your wish that he had gotten shot as, in a way, a justification for the legalization of firearms on campuses. Legalizing guns on campuses will not bring any more justice to cruel & inhumane situations or the people who bring them about. It may make it easier for people to defend themselves (or not), but justice is not served through vigilantism.
Sure, but I will also say: "If any one of those individuals was armed and trained, they could have defended themselves and his spree would have been ended." My response was directed towards the analogous case of a similar rule being applied in a different situation. Also, when did self-defense become vigilantism?
When you said you wished the man had been shot, you didn't say "I wish he'd been shot in the course of a crime." I'm willing to believe that that's what you meant to imply, but as an independent reader observing the conversation, that's not what I extrapolated from your statement. I simply saw a wish that a person had gotten shot because he had committed heinous crimes. That's why I interpreted your comment as potential vigilantism as much as potential self-defense.