150924-N-AC887-005 WASHINGTON (Sept. 24, 2015) Secretary of the Navy (SECNAV) Ray Mabus delivers remarks during a change of command ceremony at Marine Corps Barracks Washington. Gen. Robert B. Neller assumed the duties and responsibilities as the 37th commandant of the Marine Corps from Gen. Joseph Dunford. (U.S. Navy photo by Chief Mass Communication Specialist Sam Shavers/Released))