The police tape in Aurora hadn't yet cured before I'd seen this argument: if more people in that theatre had been carrying concealed weapons, as Colorado law permits, then perhaps this tragedy wouldn't have happened.
What a lovely mental image that shootout is, no? I have to admit to a bit of a thrill from the thought of society's dregs shooting at one another. It's only when I'm between them that the fantasy unravels.
Let's skip all the obvious arguments and cut to the chase: has this "arm everyone and good things will happen" strategy ever once, in all of human history, worked out?