Are Islamic State recruits more street gang members than zealots?

There are two theories why these individuals pledge allegiance to the group

The recent terrorist attacks in Spain and Finland once again compel us to ask: Who joins the Islamic State, and why?

As a professor of modern Middle Eastern history, I have spent the majority of my professional life studying the region, its culture, society and politics. In recent years, I have researched and written about IS and its terrorist activities. While other experts and I have looked at how radicalization occurs, some new ideas are emerging about how and why men are attracted to IS.

Where do the recruits come from?

We know that