Does assassinating terrorist kingpins with drone aircraft strikes really make us safer? Robert Wright looks at research suggesting that "decapitation doesn’t lower the life expectancy of the decapitated groups—and, if anything, may have the opposite effect." Obviously the killings have a short-term benefit in disrupting a terror organization, and there's no way to tell whether the group's long-term recruiting boost will outweigh that, writes Wright, but the merits of our current system are far from clear.