Responsibility for the planning of Operation Downfall fell to American commanders Fleet Admiral Chester Nimitz, General of the Army Douglas MacArthur and the Joint Chiefs of Staff—Fleet Admirals Ernest King and William D. Leahy, and Generals of the Army George Marshall and Hap Arnold (the latter being the commander of the U.S. Army Air Forces). At the time, MacArthur was also being considered for promotion to the special "super rank" of six-star General of the Armies, so as to be granted operational authority over other five-star officers. However, the proposal to promote MacArthur was only at the level of informal discussion by the time World War II ended.