US skips Kyushu, goes for Honshu

Operation Downfall had two parts: Operation Olympic, which was the planned invasion of southern Kyushu, and Olympic, which was the planned invasion of the Kanto Plain.

Over the summer, casualty projections and estimates of Japanese military strength became increasingly pessimistic. On Kyushu, the Japanese had amassed nearly a million soldiers and had stockpiled thousands of kamikaze planes.

Is it possible for the US to decide invading Kyushu will be too costly, and to instead just invade the Kanto Plain, either in the fall of 1945 or spring of 1946? Given that the Inland Sea was extensively mined and Japan's rail network would have been intensely bombed, it would have been extremely difficult to transfer the Kyushu garrisons to Honshu, and they could be left to whither on the vine.

However, I think there are some drawbacks. The Coronet invasion force might still pass close enough to Kyushu to be attacked by kamikazes, and occupying southern Kyushu would allow the US to build airfields closer to the planned Coronet landing sites (though planes launched from Iwo would still be able to reach Japan).

Also, as an alternative, did anyone consider landings on Shikoku?
 
Operation Downfall had two parts: Operation Olympic, which was the planned invasion of southern Kyushu, and Olympic, which was the planned invasion of the Kanto Plain.

Over the summer, casualty projections and estimates of Japanese military strength became increasingly pessimistic. On Kyushu, the Japanese had amassed nearly a million soldiers and had stockpiled thousands of kamikaze planes.

Is it possible for the US to decide invading Kyushu will be too costly, and to instead just invade the Kanto Plain, either in the fall of 1945 or spring of 1946? Given that the Inland Sea was extensively mined and Japan's rail network would have been intensely bombed, it would have been extremely difficult to transfer the Kyushu garrisons to Honshu, and they could be left to whither on the vine.

However, I think there are some drawbacks. The Coronet invasion force might still pass close enough to Kyushu to be attacked by kamikazes, and occupying southern Kyushu would allow the US to build airfields closer to the planned Coronet landing sites (though planes launched from Iwo would still be able to reach Japan).

Also, as an alternative, did anyone consider landings on Shikoku?

The problem with going through Kanto is the US would be hoping that invasion works like a video game and that by taking Tokyo for some reason means they win. Otherwise, it's deal with mountainous terrain for most of Honshu. Shikoku would have the same problem of they would be stuck having to maneuver through the terrain of Honshu.
 

thorr97

Banned
If the intel kept indicating an increasingly lethal Kyushu buildup of Japanese forces and if jumping to Honshu was deemed too difficult to sustain, logistically, then I think the US planners would've been more welcoming to the "blockade and starve 'em out" approach.

Thus by the spring of '46 famine would be ever present throughout the length and breadth of the Japanese home islands.
 
The reason for Kyushu was to have bases for complete air dominance and on call TACAIR for the Honshu invasion. The small islands off the main coasts and Okinawa would not support fighter bombers over Honshu, and even with Kamikazes (air and sea) eventually beat down keeping enough carriers off the coasts would still produce limited air availability. The other plus of a logistics base in Kyushu as well as anchorages for damaged ships closer than Okinawa was not unimportant. IMHO with MacArthur in charge, and Willoughby running the G2/intel shop anything short of a signed letter from Hirohito detailing dispositions in Kyushu isn't going to derail Olympic if Mac has the final say. If enough evidence accumulates, and manages to get past the "filter" at Macs HQ, then the blockade/starve scenario might be tried, with some offshore islands being seized for limited shorter range aircraft to be based there.

The elephant in the room is the fact that as long as the war goes on, even if blockade/starvation ends it in Spring, 1946, you'll have fighting everywhere else as Burma/Malaya/Singapore, DEI, FIC all need liberating and the Europeans who own those want them back, war continues in China, and Mac will be insisting on liberating all of the PI which OTL happened after the surrender. About the only places the Japanese occupied in August, 1945 that can be ignored are the various Pacific Islands where garrisons are busy starving. Still lots of allied deaths, civilians and soldiers contributing to war weariness in the USA.

Assuming Stalin declares war on more or less the same schedule as OTL, by the time Japan surrenders the USSR has all of the OTL gains in Asia adding all of Korea and all of Manchuria and a boost to Mao. Stalin might even use continuing LL to try and seize Hokkaido.

Absent the atomic bomb, nothing but bad choices...
 
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