Navy Adm. James A. Winnefeld Jr., vice chairman of the Joint Chiefs of Staff, speaks to students and spouses attending a Capstone course at the National Defense University on Fort McNair in Washington, D.C., Aug. 15, 2014. The objective of the six-week course for senior defense leaders is to improve their effectiveness in planning and employing U.S. forces in joint and combined operations. The course is mandatory for senior officers in the U.S. military.