PACIFIC OCEAN (Sept. 19, 2020) The Ticonderoga-class guided-missile cruiser USS Antietam (CG 54) fires its forward MK 45 5-inch gun during a gunnery sinking exercise (SINKEX) as part of Valiant Shield 2020. Valiant Shield is a U.S. only, biennial field training exercise (FTX) with a focus on integration of joint training in a blue-water environment among U.S. forces. This training enables real-world proficiency in sustaining joint forces through detecting, locating, tracking and engaging units at sea, in the air on land and in cyberspace in response to a range of mission areas. (U.S. Navy photo by Mass Communication Specialist 3rd Class James Hong)