USS Missouri (BB-63) ("Mighty Mo" or "Big Mo") is a United States Navy Iowa-class battleship and was the third ship of the U.S. Navy to be named in honor of the U.S. state of Missouri. Missouri was the last battleship commissioned by the United States and was best remembered as the site of the surrender of the Empire of Japan which ended World War II.

Missouri was ordered in 1940 and commissioned in June 1944. In the Pacific Theater of World War II she fought in the battles of Iwo Jima and Okinawa and shelled the Japanese home islands, and she fought in the Korean War from 1950 to 1953. She was decommissioned in 1955 into the United States Navy reserve fleets (the "Mothball Fleet"), but reactivated and modernized in 1984 as part of the 600-ship Navy plan, and provided fire support during Operation Desert Storm in January/February 1991.

Missouri received a total of 11 battle stars for service in World War II, Korea, and the Persian Gulf, and was finally decommissioned on 31 March 1992, but remained on the Naval Vessel Register until her name was struck in January 1995. In 1998, she was donated to the USS Missouri Memorial Association and became a museum ship at Pearl Harbor.

-The Korean War (1950–1953)-

In 1950, the Korean War broke out, prompting the United States to intervene in the name of the United Nations. President Truman was caught off guard when the invasion struck, but quickly ordered U.S. forces stationed in Japan into South Korea. Truman also sent U.S.-based troops, tanks, fighter and bomber aircraft, and a strong naval force to Korea to support the Republic of Korea. As part of the naval mobilization Missouri was called up from the Atlantic Fleet and dispatched from Norfolk on 19 August to support UN forces on the Korean peninsula.

Missouri arrived just west of Kyūshū on 14 September, where she became the flagship of Rear Admiral Allan Edward Smith. The first American battleship to reach Korean waters, she bombarded Samchok on 15 September 1950 in an attempt to divert troops and attention from the Incheon landings. This was the first time since World War II that Missouri had fired her guns in anger, and in company with the cruiser Helena and two destroyers, she helped prepare the way for the U.S. Eighth Army offensive.

Missouri arrived at Incheon on 19 September, and on 10 October became flagship of Rear Admiral J. M. Higgins, commander, Cruiser Division 5 (CruDiv 5). She arrived atSasebo on 14 October, where she became flagship of Vice Admiral A. D. Struble, Commander, 7th Fleet. After screening the aircraft carrier Valley Forge along the east coast ofKorea, she conducted bombardment missions from 12 to 26 October in the Chongjin and Tanchon areas, and at Wonsan where she again screened carriers eastward of Wonsan.