Pentagon Briefing Defense Secretary Dr. Mark T. Esper and Chairman of the Joint Chiefs of Staff Army Gen. Mark A. Milley brief the media at the Pentagon, Dec. 20, 2019. SHARE IMAGE: Download Image: Full Size (0.5 MB) Tags: Milley, Defense Secretary , Chairman, Esper Photo By: Marine Corps Sgt. Warren Smith, DOD VIRIN: 191220-D-MG926-022C.JPG Photo Gallery