U.S. Marine Gen. Joseph F. Dunford Jr., chairman of

U.S. Marine Gen. Joseph F. Dunford Jr., chairman of the Joint Chiefs of Staff, attends the National Defense University's 2016 Graduation ceremony, on Fort Lesley J. McNair, Washington, D.C., June 9, 2016. NDU provides Joint Professional Military Education to senior leaders of the U.S. Armed Forces and select others, which prepares students to think and operate effectively at the highest levels in an increasingly dynamic, complex, and unpredictable international security environment. DoD photo by Army Staff Sgt. Sean K. Harp/Released