Just wrote a piece on the insurgent networks in Iraq. Many initially thought it was the Baathists and then the Islamists that were the backbone of the insurgency. Neither was quite true. Iraqi Sunnis used multiple identities and experiences from their history to organize the insurgency. An example could be a cleric that came from a traditional religious family, was a former Baathist, had a relative in Iraqi intelligence, and came from an important tribe. All of those connections would be used to organize and recruit for the insurgency. Explains how you have so many former Baathists who were supposed to be seculr within IS's leadership today. Read more here.