"... While still seeing the Assad regime as an adversary based on its patron-client relationship with Iran and its implacable hostility toward Israel, U.S. decisionmakers are also dealing with the threats caused by the dramatic recent gains made in Iraq by ISIS and the influence it wields within the Syrian rebel movement. To examine these challenges, this perspective draws on a December 2013 RAND workshop to assess four possible future scenarios for the conflict in Syria: prolonged conflict, regime victory, regime collapse, and negotiated settlement. The authors update and reassess these scenarios based on developments in Syria and Iraq through August 2014 and explore the implications that each has for Syria, the region, and the United States.
Negotiated settlement was deemed the least likely of the possible scenarios.
Regime collapse, while not considered a likely outcome, was perceived to be the worst possible outcome for U.S. strategic interests..."