Johnston Atoll is an unincorporated territory of the United States, under the jurisdiction of the United States Air Force. The island is closed to public entry, and limited access for management needs is only granted by a letter of authorization from the USAF. A special use permit is also required from the United States Fish and Wildlife Service to access the island by boat or enter the waters surrounding the island, which are designated as a National Wildlife Refuge and part of the Pacific Islands Heritage Marine National Monument.Wikipedia