190410-N-SG189-1123 ATLANTIC OCEAN (April 10, 2019) Master-at-Arms 1st Class Brett Luchini fires a .25-caliber machine gun aboard the Arleigh Burke-class guided-missile destroyer USS Jason Dunham (DDG 109) during a small caliber action team exercise. Jason Dunham is participating in exercise Frontier Sentinel 19, which helps to establish conditions for security and stability in the region as Canada and the United States work closely to defend North America from rapidly evolving threats. (U.S. Navy photo by Mass Communication Specialist 3rd Class J. Keith Wilson/Released)