It’s not poverty and lack of education, according to economic research by Princeton’s ALAN KRUEGER. In the wake of the terrorist attacks on September 11, 2001, policymakers, scholars, and ordinary citizens asked a key question: What would make people willing to give up their lives to wreak mass destruction in a foreign land? In short, what makes a terrorist? A popular explanation was that economic deprivation and a lack of education caused people to adopt extreme views and turn to terrorism. For example, in July 2005, after the bombings of the London transit system, British Prime Minister Tony Blair said,...