(C-in-C). Allied command was divided into regions: by 1945, for example, Chester Nimitz was the Allied C-in-C Pacific Ocean Areas, while Douglas MacArthur was Supreme Allied Commander, South West Pacific Area, and Admiral Louis Mountbatten was the Supreme Allied Commander, South East Asia Command. A unified command was deemed necessary for an invasion of Japan. Interservice rivalry over who it should be (the United States Navy wanted Nimitz, but the United States Army wanted MacArthur) was so serious that it threatened to derail planning. Ultimately, the Navy partially conceded, and MacArthur was to be given total command of all forces if circumstances made it necessary. Considerations The primary considerations that the planners had to deal with were time and casualties—how they could force Japan's surrender as quickly as possible with as few Allied casualties as possible. Prior to the First Quebec Conference, a joint CanadianBritishAmerican planning team produced a plan ("Appreciation and Plan for the Defeat of Japan") which did not call for an invasion of the Japanese Home Islands until 1947–48. The American Joint Chiefs of Staff believed that prolonging the war to such an extent was dangerous for national morale. Instead, at the Quebec conference, the Combined Chiefs of Staff agreed that Japan should be forced to surrender not more than one year after Germany's surrender. The United States Navy urged the use of a blockade and airpower to bring about Japan's capitulation. They proposed operations to capture airbases in nearby Shanghai, China, and Korea, which would give the United States Army Air Forces a series of forward airbases from which to bombard Japan into submission. The Army, on the other hand, argued that such a strategy could "prolong the war indefinitely" and expend lives needlessly, and therefore that an invasion was necessary. They supported mounting a large-scale thrust directly against the Japanese homeland, with none of the side operations that the Navy had suggested. Ultimately, the Army's viewpoint prevailed. Physically, Japan made an imposing target, distant from other landmasses and with very few beaches geographically suitable for sea-borne invasion. Only Kyūshū (the southernmost island of Japan) and the beaches of the Kantō Plain (both southwest and southeast of Tokyo) were realistic invasion zones. The Allies decided to launch a two-stage invasion. Operation Olympic would attack southern Kyūshū. Airbases would be established, which would give cover for Operation Coronet, the attack on Tokyo Bay. Assumptions While the geography