John R. Allen, AO (born December 15, 1953) is a retired United States Marine Corps four-star General, and past Deputy Commander of U.S. Central Command, prior to serving as Commander of the International Security Assistance Force and U.S. Forces Afghanistan (USFOR-A). On 13 September 2014, the United States appointed General Allen as Special Presidential Envoy for the Global Coalition to Counter ISIL (Islamic State of Iraq and the Levant).