As you have probably read, 51 career foreign service officers in the State Department have written an internal memorandum recommending “a judicious use of stand-off and air weapons” by the United States against the Assad regime, in order to coerce Assad to comply with the February 2016 Terms for a Cessation of Hostilities–the cease-fire arrangement negotiated principally by the United States and Russia–and to “end the daily mass killing of civilians and egregious violations of human rights.”

Citation
Ashley S. Deeks & Marty Lederman, Would Airstrikes Against Assad be Lawful and Effective?: Reactions to the State "Dissent Cable", Lawfare (June 20, 2016).