sentences:  When the "Iowa"-class battleships were launched in 1943 and 1944 they carried twenty quad Bofors 40 mm gun mounts, which they used for defense against enemy aircraft.These heavy guns were also employed in the protection of allied aircraft carriers operating in the Pacific Theater of World War II.These guns remained on the battleships "Iowa, Missouri," and "Wisconsin" from the time they were commissioned until they were reactivated for service in the 1980s.