PACIFIC OCEAN (Sept. 17, 2020) Secretary of Defense Mark T. Esper, left, speaks with Cmdr. Stephen Hiers, from Houston, during a tour of the Combat Direction Center aboard Nimitz-class aircraft carrier USS Carl Vinson (CVN 70). Esper toured the ship's composite warfare commander spaces, receiving in-depth briefs on carrier strike group interoperability and naval power defense. Carl Vinson is currently underway conducting flight deck certification and carrier air traffic control center certification. (U.S. Navy photo by Mass Communication Specialist 3rd Class Aaron T. Smith)