191031-N-WI365-1126 PHILIPPINE SEA (Oct. 31, 2019) The Arleigh Burke-class guided-missile destroyer USS John S. McCain (DDG 56) fires its Mark 45 5-inch gun during a live-fire exercise. John S. McCain is assigned to Destroyer Squadron (DESRON) 15, the Navy’s largest forward-deployed destroyer squadron and the U.S. 7th Fleet’s principal surface force. (U.S. Navy photo by Mass Communication Specialist 2nd Class Markus Castaneda/Released)