According to the GAO, “the Navy relies on 11 aircraft carriers based in ports on the East and West Coasts and in Japan to support U.S. defense objectives. These nuclear-powered ships require complex maintenance that may not be available near their homeports. When a ship changes homeports, more than 5,000 people may have to move: 3,200 crew and their families. The Navy annually updates its plan for positioning its forces worldwide. Fleet commanders then identify a need for any changes to homeports and submit change requests. Maintenance—the need for a dry-dock, for example—was the driving factor for all 15 carrier homeport changes the Navy made in FYs 2011-2020.”