I was one of the posters who mentioned the idea of the SWPA as a "backwater" theater in the absence of MacArthur, but I would like to clarify that concept. If MacArthur, for whatever reason, had not commanded in the SWPA, I believe that the war in 1942 would have played out essentially as it did historically. The Japanese would still move into the islands north of Australia and the US would still react as it did, bolstering it's forces in the islands between Hawaii and Australia, and in Australia itself. Coral Sea and Midway would most likely be fought, as historically, and the Guadalcanal campaign would play out as it did in 1942-43. This is because the US definitely had to at least contain the Japanese advance toward Australia and the South Pacific. Once the Allied goal of containing the Japanese advance and securing Australia had been achieved, it's my belief that further Allied offensive activity in the SWPA would have ceased. This does not mean that there would be no combat in the area at all; The Allies would have to keep the strong Japanese forces at Rabaul neutralized and this would mean constant activity, mostly in the air, but also naval raids against that strongpoint and it's outlying bases. For that reason, considerable air and naval assets would need to be based in Australia and the lower Solomons. But the main axis of the Pacific Allied counter-offensive would have been through the Central Pacific as originally envisioned by the old war plan Orange. This required a strong carrier air component and thus would not hyave been launched until the latter half of 1943. In that sense, the Japanese would have been granted some breathing room, between the end of the Guadalcanal Campaign in February, 1943, and the invasion of Tarawa in Novenmber, 1943. But, historically, the summer of 1943 was not particularly a time in which either side launched major offnsives in the South Pacific. The Americans advanced to New Georgia in the Solomons, mainly to secure advanced bases to aid in the defense of Guadalcanal in June, and Lae-Salamaua on New Guinea was captured in early September by Austrlian and US troops to relieve the threat to southwestern New Guinea. The US needed this time to consolidate it's gains and buildup it's forces as well, so giving the Japanese some months breating space was unavoidable. Thereafter, however, the Central Pacific offensive would have occupied the attention of the Japanese Navy. It would not have mattered had the Japanese Army attempted to consolidte a strong defensive position in the SWPA, since the Allies would not have attacked in that area. In any case, the Japanese Army was primarily concerned with the war in China and it would have been unlikely to have sent much in the way of reinforcements to a "backwater" theater in which Japanese bases were being harrassed mainly by air and naval raids. The Japanese Navy was hardpressed in he Central Pacific and woud not have been able to spare many naval assets for the SWPA. After about July of 1944, the Japanese would have found it becoming increasingly difficult to keep their garrisons supplied in the SWPA and they would have either evacuated or abandoned them to their ultimate fate.