Al Qaeda - backed militants have taken control of cities in northern Iraq . Islamic State of Iraq and Syria ( ISIS ) seeks to impose a strict Islamist regime . The Al Qaeda expansion poses tough dilemma for U.S. and its European allies .
Al Qaeda-backed militants have taken control of towns in northern Syria . Islamic State of Iraq and Syria ( ISIS ) aims to impose a strict Islamist ideology . Swift al Qaeda expansion poses tough dilemma for U.S. and its European allies .