What we do know so far about Orlando: in a 911 call, the killer at the Pulse nightclub pledged allegiance to Islamic State, and he had previously expressed a fervent desire to become a “martyr.” In their speeches responding to the massacre, Hillary Clinton and Donald Trump each sought to demonstrate a firmer, clearer grasp of the jihadist menace — and therefore prove themselves best positioned to combat it. Each channeled one of the prevalent views in our culture. Both, however, are profoundly wrong. Both are united, ironically enough, in negating the crucial role of ideas in animating the jihadist cause.