Question: What is the nickname of the United States Navy battleship featured in the 1945 documentary Appointment in Tokyo?
Context: The 14"/45 caliber gun, (spoken "fourteen-inch-forty-five-caliber"), whose variations were known initially as the Mark 1, 2, 3, and 5, and later as the Mark 8, 9, 10, and 12, were the first 14 in guns to be employed with the United States Navy, and were for over a year the most powerful naval ordnance afloat.  They were installed aboard the United States Navy's "New York"-class , "Nevada"-class , and "Pennsylvania"-class battleship s as the primary armament for each battleship in the class.  The gun also saw service in the British Royal Navy, where it was designated the BL 14 inch gun Mk II. USS "South Dakota" (BB-57) was a battleship in the United States Navy, in active service from 1942 until 1947.  The lead ship of her class, "South Dakota" was the third ship of the US Navy to be named in honor of the 40th state.  The four ships of the class are considered to be the most efficient battleships designed under the limitations of the Washington Naval Treaty.  During World War II, the battleship first served a tour in the Pacific theater, where it fought in two battles in 1942 that earned the ship and its crew a Navy Unit Commendation before returning to New York in December 1942 for an overhaul and battle repairs.  In May 1943, "South" "Dakota" joined British Home Fleet patrols in the North Atlantic and Arctic Oceans before sailing again to the Pacific in August 1943.  There, "South Dakota" participated in combat operations preparatory to the invasion of Japan until returning to the United States in October 1945. Appointment in Tokyo is a 1945 documentary released Produced by the Army Pictorial Service, Signal Corps, with the cooperation of the Army Air Forces and the United States Navy, and released by Warner Bros. for the War Activities Committee shortly after the surrender of Japan.  It mainly follows General Douglas MacArthur and his men from their exile from the Philippines in early 1942, through the signing of the instrument of surrender on the USS "Missouri" on September 1, 1945. USS "Iowa" (BB-4) was a United States Navy battleship.  It was the first ship commissioned in honor of Iowa and was America's first seagoing battleship.  "Iowa" saw substantial action in the Spanish–American War.  While she was an improvement over the "Indiana" class because of a superior design, the warship became obsolete quickly in the first quarter of the 20th century and was used for target practice and sunk on 23 March 1923 in Panama Bay by a salvo of 14-inch shells. The USS "Iowa" turret explosion occurred in the Number Two 16-inch gun turret of the United States Navy battleship  on 19 April 1989.  The explosion in the center gun room killed 47 of the turret's crewmen and severely damaged the gun turret itself.  Two major investigations were undertaken into the cause of the explosion, one by the U.S. Navy and then one by the General Accounting Office (GAO) and Sandia National Laboratories.  The investigations produced conflicting conclusions. 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 after the U.S. state of Missouri.  "Missouri" was the last battleship commissioned by the United States and is best remembered as the site of the surrender of the Empire of Japan which ended World War II. A Glimpse of Hell: The Explosion on the USS "Iowa" and Its Cover-Up is a nonfiction book of investigative journalism, written by Charles C. Thompson II and published in 1999.  The book describes the USS "Iowa" turret explosion that took place on April 19, 1989, and the subsequent investigations that tried to determine the cause.  The explosion aboard the United States Navy battleship "Iowa" killed 47 of the turret's crewmen. USS "Delaware" (BB-28) was a dreadnought battleship of the United States Navy, the lead ship of her class.  She was laid down at Newport News Shipbuilding in November 1907, launched in January 1909, and completed in April 1910.  The sixth ship to be named for the First State, "Delaware" was armed with a main battery of ten 12 in guns all on the centerline, making her the most powerful battleship in the world at the time of her construction.  She was also the first battleship of the US Navy to be capable of steaming at full speed for 24 continuous hours without suffering a breakdown. USS "New York" (BB-34) was a United States Navy battleship, the lead ship of her class.  Named for New York State, she was designed as the first ship to carry the 14 in /45-caliber gun. The attack on Yokosuka was an air raid conducted by the United States Navy on 18 July 1945 during the last weeks of the Pacific War.  The Japanese battleship "Nagato" was the raid's main target, though anti-aircraft positions and other warships at Yokosuka Naval Arsenal were also attacked.  Other U.S. Navy and British Royal Navy aircraft struck airfields in the Tokyo area.
Answer: Mighty Mo