The country of Iraq is somewhat of an artificial creation going back to colonial days. And so you have the Kurds and then the Sunnis in the north predominantly and Shias in the south.

If ISIL were to substantially increase the priority it places on attacking the West rather than fighting to maintain and expand territorial control, then the group's access to radicalized Westerners who have fought in Syria and Iraq would provide a pool of operatives who potentially have access to the United States and other Western countries.

The term 'Muslim Brotherhood'... is an umbrella term for a variety of movements: in the case of Egypt, a very heterogeneous group, largely secular, which has eschewed violence and has decried Al Qaeda as a perversion of Islam.

James Clapper Quotes