Esper and Milley Defense Secretary Dr. Mark T. Esper and Army Gen. Mark A. Milley, the chairman of the Joint Chiefs of Staff, speak to reporters at the Pentagon, March 2, 2020. SHARE IMAGE: Download Image: Full Size (4.5 MB) Tags: Milley, Defense Secretary , Chairman, Esper Photo By: Lisa Ferdinando, DOD VIRIN: 200302-D-BN624-0115.JPG Photo Gallery