U.S. Defense Secretary Chuck Hagel, center right, walks with Kuwaiti Army Chief of Staff Lt. Gen. Mohammad Al-Khoder as...

U.S. Defense Secretary Chuck Hagel addresses service members on Forward Operating Base Gamberi, Afghanistan, Dec. 7,...

U.S. Army Gen. Martin E. Dempsey, chairman of the Joint Chiefs of Staff, and his wife, Deanie, open a USO show for U.S....

U.S. Army Gen. Martin E. Dempsey, chairman of the Joint Chiefs of Staff, takes a photo with a U.S. sailor while aboard...

U.S. Defense Secretary Chuck Hagel visits U.S. service members at the International Security Assistance Force dining...

U.S. Defense Secretary Chuck Hagel, left, and Afghan President Ashraf Ghani conduct a joint press conference at the...

U.S. Defense Secretary Chuck Hagel, center left, meets with Afghan President Ashraf Ghani, center right, to discuss...

Defense Secretary Chuck Hagel briefs reporters on board an aircraft as they travel to Afghanistan, Dec. 5, 2014.

Defense Secretary Chuck Hagel waves goodbye as he boards an aircraft to depart Joint Base Andrews, Md., Dec. 5, 2014,...

Deputy Defense Secretary Bob Work, left, stands with Army Gen. Charles H. Jacoby Jr. during a change-of-command...