WI: Operation Downfall happens?

So... basically I'm planning to write and publish a story on a certain site (which is not AH.com, unfortunately) set in an alternate universe where the US had executed Operation Downfall.

As far as I can tell, an alternate Downfall means a) Manhattan Project sees little to no progress, b) the US decides to invade Japan instead of blockading it, and c) Japan thinks the Americans or Soviets will kill their divine emperor, so they opt to fight to the death.

And here's what I know will happen: a) lots of American soldiers die, b) even more Japanese civilians die from starvation/suicide attacks/atrocities/etc, and c) the loss of American lives means the US will not let Emperor Hirohito live (at least the angry soldiers won't, even if they're commanded not to kill him by higher-ups). Unfortunately, this means a lot more tension between the occupying US and the defeated Japanese civilians. Not to mention the Soviets overwhelming Korea and northern Japan.

After that, we have a north/south Japan. The question is whether war will erupt between the two (which I personally think is very likely).

I'd appreciate your feedback on how plausible/likely the scenarios above are, as well as details regarding Operation Downfall and the American invasion/liberation of Tokyo. Feel free to link to external sources (preferably free-to-access websites, but books and documentaries are also welcome).

Have a great day, folks.
 
So... basically I'm planning to write and publish a story on a certain site (which is not AH.com, unfortunately) set in an alternate universe where the US had executed Operation Downfall.

As far as I can tell, an alternate Downfall means a) Manhattan Project sees little to no progress, b) the US decides to invade Japan instead of blockading it, and c) Japan thinks the Americans or Soviets will kill their divine emperor, so they opt to fight to the death.

And here's what I know will happen: a) lots of American soldiers die, b) even more Japanese civilians die from starvation/suicide attacks/atrocities/etc, and c) the loss of American lives means the US will not let Emperor Hirohito live (at least the angry soldiers won't, even if they're commanded not to kill him by higher-ups). Unfortunately, this means a lot more tension between the occupying US and the defeated Japanese civilians. Not to mention the Soviets overwhelming Korea and northern Japan.

After that, we have a north/south Japan. The question is whether war will erupt between the two (which I personally think is very likely).

I'd appreciate your feedback on how plausible/likely the scenarios above are, as well as details regarding Operation Downfall and the American invasion/liberation of Tokyo. Feel free to link to external sources (preferably free-to-access websites, but books and documentaries are also welcome).

Have a great day, folks.
There is a case to be made that the Soviet Invasion of Japanese-occupied Manchuria was as (I am not saying the nukes weren't important as well!) important as Hiroshima and Nagasaki in convincing the Japanese to surrender. The Japanese had been holding on for some time in the mistaken belief that the Soviets could potentially act as a mediator for a more palatable peace settlement, and the Japanese had contemplated similar terms to those that they eventually accepted after the atomic bombs fell, both with the caveat that the Emperor be spared. The Soviet Invasion of Manchuria forced the Japanese to reconsider their position, or risk getting similar treatment as Nazi Germany (a partition into Soviet and American occupation zones).
 
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Potentially Japanese Army units could fight each other over supplies. this would become more common as the chain of command disintegrates.
The Japanese military expanded most of its automatic weapons and the vast majority of its heavy artillery defending Okinawa. The American military would be better equipped and prepared to dig the Japanese out of entrenched positions.
American casualties would be lighter than expected and Japanese casualties would be heavier.
if it gets real dirty and the Japanese decide to use bacteriological weapons, the Americans would resort to poison gas which being heavier than air tends to concentrate in caves and other below-ground structures.
 
I'm actually not too optimistic about the chances of Operation Downfall succeeding.


The japanese were well prepared, their forces on Kyushu allmost equaled that of the american invasion fleet in numbers, they correctly predicted where and when the americans would land and kamikaze attacks were assumed to be very effective. Overall, Operation Downfall could end in a crushing defeat for the United States, the implications of which are unpredictable.
 
I'm actually not too optimistic about the chances of Operation Downfall succeeding.


The japanese were well prepared, their forces on Kyushu allmost equaled that of the american invasion fleet in numbers, they correctly predicted where and when the americans would land and kamikaze attacks were assumed to be very effective. Overall, Operation Downfall could end in a crushing defeat for the United States, the implications of which are unpredictable.
I personally think that this results in some kind of a "tie" with the Western Allies (Unless an alternative come up; say that the US waits to see how this operation goes to decide on using the bombs or not.) How this plays out with the Soviet Union I do not know. I suspect maybe that it entails Japan giving up some mainland Asian territory to the Soviets (If not all of it.), and mainland Japan then staying safe.
 

Ficboy

Banned
If Operation Downfall happened it would result in hundreds of thousands more dead in Japan (Allied or Japanese) and the result would be the D-Day of the Pacific not to mention World War II would be extended to 1946.
 
So... basically I'm planning to write and publish a story on a certain site (which is not AH.com, unfortunately) set in an alternate universe where the US had executed Operation Downfall.

As far as I can tell, an alternate Downfall means a) Manhattan Project sees little to no progress, b) the US decides to invade Japan instead of blockading it, and c) Japan thinks the Americans or Soviets will kill their divine emperor, so they opt to fight to the death.

And here's what I know will happen: a) lots of American soldiers die, b) even more Japanese civilians die from starvation/suicide attacks/atrocities/etc, and c) the loss of American lives means the US will not let Emperor Hirohito live (at least the angry soldiers won't, even if they're commanded not to kill him by higher-ups). Unfortunately, this means a lot more tension between the occupying US and the defeated Japanese civilians. Not to mention the Soviets overwhelming Korea and northern Japan.

After that, we have a north/south Japan. The question is whether war will erupt between the two (which I personally think is very likely).

I'd appreciate your feedback on how plausible/likely the scenarios above are, as well as details regarding Operation Downfall and the American invasion/liberation of Tokyo. Feel free to link to external sources (preferably free-to-access websites, but books and documentaries are also welcome).

Have a great day, folks.

Just have the Kyujo Incident succeed, that's all thats needed for Operation Downfall.

As for the effects, Operation OLYMPIC was heading for certain failure, with likely close to a million Allied casualties. The Soviet invasion of the Kuriles was already collapsing, and their battle plan for Manchuria had likewise. It'll take until 1946 for the Red Army to clear the IJA out of Manchuria and Korea both, and likely at the cost of nearly a million causalities. Outside of those theaters, the IJA remained strong in both China and Southeast Asia with millions of troops under arms.
 
There is a case to be made that the Soviet Invasion of Japanese-occupied Manchuria was as important as Hiroshima and Nagasaki in convincing the Japanese to surrender. The Japanese had been holding on for some time in the mistaken belief that the Soviets could potentially act as a mediator for a more palatable peace settlement, and the Japanese had offered the U.S. very similar terms to those that they eventually accepted after the atomic bombs fell, both with the caveat that the Emperor be spared. The Soviet Invasion of Manchuria forced the Japanese to reconsider their position, or risk getting similar treatment as Nazi Germany (a partition into Soviet and American occupation zones).

Kōichi Kido, Lord Keeper of the Privy Seal for the Emperor, kept diaries and they reveal the decision on the part of the Emperor to seek peace came before the entry of the Soviets, due to the August 6th atomic bombing. As it were, while the Soviets achieved operational surprise due to the efforts of the U.S. under Operation MILEPOST and HULA, they did not achieve strategic surprise; the Japanese were already expecting the Soviets to enter the war, as such was obvious after Moscow terminated their Non-Aggression Pact. What did catch the Japanese off guard was how American logistical aid allowed the Soviets to mount their attack so much earlier than expected.

Finally, it is a myth the Japanese were offering peace under the terms they got IOTL:

"The most often repeated condemnation of American diplomacy in the summer of 1945 is that policy makers understood that a promise to retain the Imperial institution was essential to end the war, and that had the United States communicated such a promise, the Suzuki cabinet would likely have promptly surrendered. The answer to this assertion is enshrined in black and white in the July 22 edition of the Magic Diplomatic Summary. There, American policy makers could read for themselves that Ambassador Sato had advised Foreign Minister Togo that the best terms Japan could hope to secure were unconditional surrender, modified only to the extent that the Imperial institution could be retained. Presented by his own ambassador with this offer, Togo expressly rejected it. Given this, there is no rational prospect that such an offer would have won support from any of the other live members of the Supreme Council for the Direction of the War. - (Frank 1999, p. 239)"​
"As historian Robert Butow pointed out in 1954, the fate of Japan rested in the hands of only eight men. These were the emperor, his principal advisor Marquis Koichi Kido, and an inner cabinet of the government of Admiral Kantaro Suzuki called the "Big Six": Prime Minister Suzuki, Foreign Minister Shigenori Togo, Army Minister General Korechika Anami, Navy Minister Admiral Mitsumasa Yonai, Chief of the Army General Staff General Yoshijiro Umezu, and Chief of the Navy General Staff Admiral Soemu Toyoda.​
There is no record whatsoever that any of these eight men proposed a set of terms or circumstances in which Japan would capitulate prior to Hiroshima. More significantly, none of these men even after the war claimed that there was any set of terms of circumstances that would have prompted Japan to surrender prior to Hiroshima. The evidence available shows that in June, a memorandum from Kido to the emperor proposed that the emperor intervene not to surrender, but to initiate mediation by a third party. The mediation would look to settle the war on terms that echoed the Treaty of Versailles: Japan might have to give up its overseas conquests and experience disarmament for a time, but the old order in Japan would remain in charge. Certainly there would be no occupation and no internal reform. - (Richard B. Frank 2009)"​
 
If Japan fights on after the Soviets attack and two nukes, it gets bad. Even if the US holds off on dropping additional nuclear bombs, the USAAF had enough B-29 units in the Pacific already, and a number of units coming from England, that round the clock conventional bombing is going to be a thing for months going forward. Going into the end of 1945 and into 1946, a lot of Japanese civilians are going to starve to death or die of disease as society collapses
 
The japanese were well prepared, their forces on Kyushu allmost equaled that of the american invasion fleet in numbers, they correctly predicted where and when the americans would land and kamikaze attacks were assumed to be very effective. Overall, Operation Downfall could end in a crushing defeat for the United States, the implications of which are unpredictable.
But they had virtually no fuel for any of the weapons. They would have definitely caused horrendous casualties, but it still wouldn't have ended well for the Japanese. There's only so much a spear can do against a Sherman tank.
 
I wonder what'd happen in the aftermath of a successful Downfall. Perhaps the US administration, traumatized by the losses incurred upon its military by the invasion, decides to cut its losses and make its control area over Asia spread in a smaller territory compared to the communist bloc?
 
One thing that often gets overlooked with the invasion of Japan is that every month we’re at war with Japan 400,000 Chinese, Vietnamese, Korean, and various other countries civilians are dying from occupation. It’s interesting because you could justify the atomic bombings with just this information and not even mention American casualties.

 
I'm actually not too optimistic about the chances of Operation Downfall succeeding.


The japanese were well prepared, their forces on Kyushu allmost equaled that of the american invasion fleet in numbers, they correctly predicted where and when the americans would land and kamikaze attacks were assumed to be very effective. Overall, Operation Downfall could end in a crushing defeat for the United States, the implications of which are unpredictable.
Earlier Kamikaze had been done by airmen that had flown against USA earlier in the war IIRC. If the Japanese send up a bunch of untrained pilots against the USA the veteran airmen will have another Marianas turkey shoot.
 
IIRC the Americans were to send a decoy landing fleet in first to soak up kamikazees. The Americans would have every carrier avalible with fighters and Okinawa and Iwo would be filled with long range fighters.
 
I'm not exactly sure how effective the kamikazes would be. The Americans intended to take islands near Japan to use as forward Air bases to give air cover for the invasion. Japan had no plans on defending those islands.
come invasion time to Japanese airfields would have been buried three layers deep in fighter-bombers.
The engines on the Kamikaze aircraft were turned over once a week to make sure they were working, but that wasn't enough to spot any flaws that would show up after a minute or two of flight. Japan used train pilots the Kamikaze attacks of Okinawa, for the defense of Japan they would be using raw recruits with a little or no actual flight experience. Then there is the matter of fuel, the Japanese had enough fuel for their kamikazes but there's a good chance some of the fuel would have been stolen or have been lost to leakage.
 
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Earlier Kamikaze had been done by airmen that had flown against USA earlier in the war IIRC. If the Japanese send up a bunch of untrained pilots against the USA the veteran airmen will have another Marianas turkey shoot.
IIRC the Americans were to send a decoy landing fleet in first to soak up kamikazees. The Americans would have every carrier avalible with fighters and Okinawa and Iwo would be filled with long range fighters.
I'm not exactly sure how effective the kamikazes would be. The Americans intended to take islands near Japan to use as forward Air bases to give air cover for the invasion. Japan had no plans on defending those islands.
come invasion time to Japanese airfields would have been buried three layers deep in fighter-bombers.
The entrance on the Kamikaze aircraft were turned over once a week to make sure they were working, but that wasn't enough to spot any flaws that would show up after a minute or two of flight. Japan used train pilots the Kamikaze attacks of Okinawa, for the defense of Japan they would be using raw recruits with a little or no actual flight experience. Then there is the matter of fuel, the Japanese had enough fuel for their kamikazes but there's a good chance some of the fuel would have been stolen or have been lost to leakage.

IGHQ had been stockpiling aviation fuel for months in preparation for the invasion, with total inventory being 1,156,000 barrels by July of 1945. Much the same had been done for pilots, with IJA having 2,000 pilots with at least 70 hours of flying time while the IJN had 4,200 on hand who were considered sufficiently trained for night or low light missions; given the type of challenges those conditions presented, that means they were well trained. Overall, when the Japanese formulated KETSU-GO starting in July of 1945, the plan called for 9,000 aircraft to be brought to bare against the invasion fleet. Contemporary to this, the Japanese inventory already contained 8,500 ready planes and IGHQ expected another 2,000 by the fall. When the Allies conducted a census in August following the surrender they found 12,684 aircraft of all types in Japan, suggesting that IGHQ's estimates were spot on for 10,500 aircraft by November. As for planned uses, of the 9,000 to be used in KETSU-GO, kamikazes were to comprise 6,225 of the total.

That last bit is perhaps the most important, as experience at Okinawa had shown that a 6:1 ratio existed in the expenditure of kamikazes to achieve a successful ship sinking. Japanese planning held, and U.S. estimates agree with them, that they believed in the initial 10 days of the invasion they could sink at least 500 transports out of the expected 1,000 the U.S. was bringing for the attack. This would've amount to the loss of about five divisions and much of the logistical network, crippling the invasion before it even stormed the beaches. There is every reason to believe this would've worked, as the Japanese would've enjoyed several advantages they didn't have at Okinawa, such as:
  1. The mountainous terrain meant that Japanese attacking aircraft would've been shielded from radar detection almost until they were right up on the fleet. At Okinawa, the U.S. had been able to deploy destroyers as pickets dozens of miles out but that wouldn't have possible here because the invasion fleet obviously had to be closely anchored off Japan.
  2. The "Big Blue Blanket", which was an Anti-Kamikaze tactic devised by the U.S. during Okinawa, involved masses of fighters kept aloft and being fed data by the picket ships. However, this would've been impossible to counter the Japanese here, as the U.S. was only bringing 5,000 total aircraft from the Far Eastern Air Force in the Ryukyus and the carriers of the 3rd and 5th Fleets. The problem, as outlined by Giangreco, was that U.S. planning called for TF-58 with its 1,900 plans to be 600 miles to the North attacking targets in Honshu instead of supporting the 7th Fleet. This left just two carrier groups to provide a combat air patrol for the fleet, which means that American fighters would've been outnumbered by the Japanese by about a staggering 10 to 1. In other words, even if every American fighter pilot became an ace during those first 10 days, thousands of Japanese aircraft would've still broken through.
  3. The Japanese had 60 airfields on Okinawa and the aforementioned fact of short distances to target meant that mechanical issues, a problem that plagued kamikaze operations during Okinawa given the hundreds of miles distance from Japan to the island, would not have been anywhere near as prevalent.
 
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