Gary Brecher:

In fact, ISIS’s quarrel with Zawahiri was a lot like a corporate boardroom feud. It’s always worth remembering that Jihadis are just friggin’ people, and their disagreements tend to be about very ordinary organizational issues. Granted, it’s a little harder to see that when they solve those disagreements with public beheadings and overly-cinematic rituals, but at heart this is just standard human behavior—primates squabbling for rank and power, Game of Thrones with Islamic voiceover.

…

But when you have 1,200 different factions to deal with, you have at least 1,200 egos to massage, and every damn one of them has a few dozen, or a few hundred, men ready to kill, and die, at his command. These nay-sayers were not in the mood to let some Iraqi interloper take over the Syrian revolution, and insisted on localizing what ISIS saw as the inherently universal mandate of jihad. The local/universal tension is deep in Islam, which borrowed Christianity’s universalizing mandate. In theory, a Chechen who knows the Quran is as entitled to tell a Syrian what to do as anyone else. In practice, he’s a jerk, and if he tells you to do things a different way than your family has done them for generations, you don’t care how many verses he can quote at you. You’re pissed off

…

So out of all this chaos and blood comes something like a vindication of the laws of physics, as expressed in ethnic turf wars. But with one modification of those laws: Some things really don’t abhor a vacuum, especially transnational ethnic militias. They love a vacuum more than Alice did on the Brady Bunch.

-- http://pando.com/2014/06/16/the-war-nerd-heres-everything-you-need-to-know-about-too-extreme-for-al-qaeda-i-s-i-s/