Columbine; Port Arthur, Australia; The Sikh Temple of Wisconsin; Newtown — the list goes on and on. And, by now, the elements of this type of massacre have become ritualized: usually one, but sometimes more than one, deeply disaffected person, almost always male, who is heavily armed with guns and/or explosives, targets the innocent. In the aftermath, which sometimes includes a trial, the crucial question of "Why?" is never really answered. Instead, most of us are left to wonder how any human being, however twisted, could be capable of such horror.