The economics of radical religious terrorism

The Charlie Hebdo attack has led many to claim that - or at least question why - Islam is associated with terrorism. I would reverse the order of causality the question implies. We must first try to answer why there are so many terrorist organizations linked to radical Islam.

According to a book I read over the weekend, it turns out that is not a correct statement either. In his 2009 book ?Radical, Religious and Violent: The New Economics of Terrorism,? economist Eli Berman starts by dispelling some myths: Contrary to popular belief, radical Islamist terrorists are not motivated by the promise of rewards in the afterlife or even by religious ideals. They are best understood as ?rational altruists seeking to help their own communities.?

When looked through this lens, you immediately notice that terrorist organizations have millions of potential recruits ? young altruists who feel that their communities are repressed or endangered. Then, you begin to wonder not why there are so many terrorist organizations associated with radical Islam, but why there are so few. In fact, less than a dozen such organizations are active today. But all of them are extremely lethal, and - as cold as it may sound - "successful."

To understand why that is the case, it may be useful to look at unsuccessful religious terrorists. The Jewish Underground, a group of Orthodox Jewish settlers who targeted civilian Arabs and Muslim holy sites in the 1980s, was quickly uncovered by Israeli intelligence. Berman explains that ?its members leaked information, leading to infiltration by the authorities.?

We can also gain some insight from religion in the U.S.: In an influential 1994 paper titled ?Why Strict Churches are Strong,? economist Laurence Iannaccone argues...