The videotaped beheading of American journalist James Foley by an Islamic State militant has opened the eyes of the public to what Middle East experts have known for some time: As terrorists go, the barbaric, single-minded zealots of the Islamic State (aka ISIS or ISIL) are in a category all their own. Quartz’s Bobby Ghosh has compared them to Al Qaeda, the Khymer Rouge, and even the Nazis. The Nazi comparison should almost always be avoided, but the hyperbole is perhaps apt in this case. Just as the Nazis’ unique brand of evil set it apart from other authoritarian and fascist movements, so is ISIS uniquely different from—and more malignant than—terrorist groups that have come before it.
The Islamic State now controls huge swaths of territory in Iraq and Syria, and continues to probe the borders of Iraqi Kurdistan and Lebanon. As my co-author Brian Fishman and I have noted even before the sweeping attacks on Mosul and Tikrit, ISIS is a de facto state and safe haven in which terrorists can train—an environment perhaps even more threatening than pre-9/11 Afghanistan. And they’re only getting more popular, with thousands of new recruits joining just this month.