“In early July, Defense Secretary Ash Carter said he didn’t know whether the U.S. military could defend the Syrian opposition fighters it is training and equipping as its proxy ground force. Now, as the month draws to a close, the White House is preparing to fly strike missions from Turkish air bases against ISIS, and is backing a ‘safe zone’ to clear ISIS away from Turkey’s border with Syria. All of this raises the distinct possibility of clashes with Syrian government forces — yet Pentagon leaders don’t yet know whether they have the legal authority to order U.S. troops to fight.”
Source: Pentagon Doesn’t Know If It’s Allowed to Defend Syrian Fighters or Turkish ‘Safe Zone’ – Defense One