Porter has written on the use of chemical weapons in the Syrian civil war, including the Ghouta chemical attack which occurred during the Syrian Civil War. Porter wrote in September 2013 about the origins and content of the White House intelligence report entitled "U.S. Government Assessment of the Syrian Government's Use of Chemical Weapons on August 21, 2013", commenting that analysis by Inter Press Service (IPS) and interviews with former intelligence officials indicated the report only consisted of White House-selected information, and failed to accurately reflect the opinions of intelligence analysts. He queried the "assumption that it was a Syrian government-sponsored attack" by asserting that "significant new information has become available that makes an attack by opposition forces far more plausible than appeared to be the case in the first weeks after the event."