Inquiring Minds

"Its Islam over everything."So read the Twitter bio of Douglas McAuthur McCain—or, as he reportedly called himself, "Duale Khalid"—the San Diego man who is apparently the first American to be killed while fighting for ISIS. According to NBC News, McCain grew up in Minnesota, was a basketball player, and wanted to be a rapper. Friends describe him as a high school "goofball" and "a really nice guy." So what could have made him want to join the ranks of other Americans drawn towards militant Islam like John Walker Lindh and Al Qaeda spokesman Adam Yahiye Gadahn? And how can we explain the dozens of other Americans who have also gone off to fight as jihadists in Syria, for ISIS and other militant groups?According to University of Maryland psychologist and terrorism expert Arie Kruglanski, who has studied scores of militant extremists, part of the clue may lie in that Twitter tagline of McCain's. Not just its content, but the mindset that it indicates—one that sees the worl