"The rise of the insurgent terrorist group known as the Islamic State (IS, aka the Islamic State of Iraq and the Levant or ISIL/ISIS) and Russia's military intervention on behalf of the Syrian government have reshaped debates over U.S. policy toward the ongoing civil conflict in Syria, now in its sixth year. The Islamic State controls large areas of northeastern and central Syria, from which it continues to launch assaults on forces opposed to and aligned with the government of President Bashar al Asad. Meanwhile, fighting elsewhere pits government forces and their foreign allies against a range of anti-government insurgents, some of whom have received limited U.S. assistance. Russian military intervention in support of Asad poses a direct challenge to U.S. goals in Syria, and is raising new questions about the future of the conflict and U.S. strategy."
CRS Report for Congress, RL33487
Federation of American Scientists: http://www.fas.org/sgp/crs/index.html