Acting Secretary of Defense Patrick M. Shanahan (center) serves as the presiding official during the U.S. Central Command change of command ceremony, March 28, 2019. Army Gen. Joseph L. Votel (left) was relieved by Marine Corps Gen. Kenneth F. McKenzie (right), who previously served as the Director of the Joint Staff. (DoD Photo by Navy Petty Officer 1st Class Dominique A. Pineiro)