Canada's lone operational submarine recently took part in a massive military exercise involving 30 nations. On July 12, its mission was to sink a decommissioned U.S. warship off Hawaii. HMCS Corner Brook shot a torpedo at USS Mobile Bay. Thirty ships, five submarines, 15 national land forces, more than 190 aircraft and more than 30,000 personnel took part in RIMPAC 2026 around the Hawaiian Islands from June 24 to July 31.