Council on Foreign Relations
New America:
"For al-Qaeda, attaching its name to Zarqawi's activities enabled it to maintain relevance even as its core forces were destroyed [in Afghanistan] or on the run," wrote Brian Fishman, a counterterrorism fellow at the New America Foundation.
At odds with al-Qaeda's aims, ISIS has since expanded its territorial control, establishing a "de facto state in the borderlands of Syria and Iraq" that exhibits some of the traditional markers of sovereignty, note Douglas Ollivantand Fishman.