Magic, Ultra, and Operation Olympic

Imagine an alternate TL in which the Manhattan project was either delayed for a year or so, and the United States was not aware of the extent of Japanese buildup on Kyushu to repel the allied invasion or at least make it extraordinarily costly. Without the intelligence provided by decoded Japanese communications, there was an excellent chance Operation Olympic might have been mounted against far greater odds, both on the ground and in kamakazi defenses, than planned.

Although they realized the war was effectively lost, the Japanese intended to place a final all-out and suicidal effort into the defense of Kyushu, hopefully to defeat the invasion and force a negotiation of peace far more lenient than an unconditional surrender. In this context, it is also important to remember that US units slated for Olympic had losst a fair degree of unit cohesion by the demolbilization and reassignment processes instituted after VE day.

If the invasion failed - or became a hopless morass - what would this do to US morale and the ultimate course of the war. Was the Japanese hope to force a Versailles-like settlement completely unrealistic or could this have occurred? Would the Soviets have just marched into lightly defended Hokaiddo and eventually gobbled up most of lightly defended Japan anyway? Would there even be a Japan today?
 
You would see the US turn its who might on the Japanies instead of about 15% of the Production . Think of the Japaniese home islands turned into a traget range for the US Army Air corps and US Navy . As it is you have killed of my father Norberts Uncle and alot of others Board members Grand Fathers and Great Uncles . When the US finly lands troops on Japan think of the US treating the Home islands as the Did okanowa. I'm not sure the Japaniese pople would servive the Battle .
 

CalBear

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We had this POD come up a few times of late.

Operation Olympic is likely to be delayed due to damage cause by the October '45 typhoons. This would give allied planners more time to develop what was already being considered, a straight jump to Operation Coronet. (This was based on the degree of build-up by the IJA near the Kyushu invasion beaches that had been detected. These troop movements had stripped the defenses of the rest of the Home Islands). This would mean that Honshu falls in early '46 and the Japanese troops on Kyushu are left (along with much of the civilian population) to starve or surrender, their choice

A second option is allowing a significant percentage of the Japanese civilian population starves to death by the spring of 1946, while the cities of Hiroshima & Nagasaki (along with the other cities on the "saved" list) are utterly destroyed by fire bombings. The transferred crews of the Mighty 8th begin to conduct bombing raids over Kyushu, freeing up the B-29 squadrons to wreak even more havoc on Honshu.

No bombs means, at worst, an additional 250,000 American casualties (Assuming the original Olympic proceeds, which is fairly unlikely) and an additional 5-6 MILLION Japanese deaths, many from starvation and disease as the blockade runs its course (google a copy of the USAAF Pacific Strategic Bombing Survey and take a look, the projections are chilling) and from the ongoing firebombings. Even without the blockade and ongoing bombings, there were a surprisingly large numbers of starvation related deaths in Japan during the winter of '45/'46.
 
Would the Soviets have just marched into lightly defended Hokaiddo and eventually gobbled up most of lightly defended Japan anyway?
This always seems to come up, But I have never seen any evidence that Russia was planning to invade Japan.

I do think that without 'The Bomb', Russia would have gotten all of Korea.

August 6th 1945
The first of the so called 2000 plane raids approaches Hiroshima. so far relitivily untouched by the war.
flying about 100 feet between wing tips the 200 planes in front cover a strip 4 miles wide,.
As the first planes cross the docks they release their loads [incenaries & explosive], followed in sequence by the ten following waves.

By the time the resulting firestorm ends the next day over 75,000 people have died. and another 50,000 are in critical condition.

August 13 th
The firebombing of Hiroshima is repeated at Nagasaki with some 40,000 dead and 25,000 in critical condition.
This would be the pattern for the next three months.

Septembre
Japanese withdraw from China Complete, Japanese begin withdraw from Manchuria into Korea.

Octobre
The Bombing turns to Kyushu , where the Japanese have some fourteen divisions and various smaller formations, including three tank brigades, for a total of 900,000 men.
From Studabaker in the east to Parkard in the west, Daily bomb attacks covering 4 mile wide by 3~4 mile deep demolish the beaches.
Other attacks demolish the cities, towns and Villages, as well as all transport besides walking.

Novembre
Major Kamikaze [Typhoon] hits Okinawa, Thousands of Men and millions of dollars of equipment, including Capital ships, and Planes are destroyed.
The bombing stops temperary will the Invasion is postponed till March.

January 1946
The bombing raids resume, concentrating on Japan's abillitily to move around the country, and focused on the south,
Roads, Bridges, Railways, Paths, & Trails, If it is moving the reconnisence planes spot it, and the B-29's attack it.

Febuary 1946
The Focus returns to Kyushu, while the delay allowed the Japs to rebuild, the delay has also burned months worth of Food,
Without Japan being able to resupply the forces on Kyushu, most of the troops are Starving.
Russians reach Pusan

March 1 1946 X-5
Us troops invade the offshore islands of Tanegashima, Yakushima, and the Koshikijima Islands,
This is to provide anchorages for ships while waiting and to supply some emerency landing strips for damaged planes.

March 2nd 1946 X-4
Seabees move into the offshore islands and begin construsting Landing strips.

March 3rd 1946 X-3
Several hundred Allied ships approach Miyazaki, Ariake, and Kushikino.
[If a clock were drawn on a map of Kyūshū, these points would roughly correspond to 4, 5, and 7 o'clock, respectively]
Japan reponds by launching 800 small suicide tordedo boats, and 1200 miget submarines, along with 3000 kamakaze planes.
The orders are to target the Troops ships, except this is a feint by the allies.
The Fleets consist of several Battleships/Battlecrusiers surrounded by several hundred anti aircraft Destroyers, and PT boats.

Several miles behind are a dozen US and Commonwealth Aircraft carriers.
While the Allies lose several destroyers and PT boats, along with several dozens of planes, The Japs lose 80% of their kamizize forces.


March 4th 1946 X-1

The Navy begins a 24 hour bombardment of the 35 expected landing beaches, the B-29's begin mass bombing of anyplace the Reconisence has any idea of the Japs having reinforcements in the centre of the island.

March 5th X-Day
35 Corps hit the Landing Beaches, From Austin, Buick, Cadillac through Stutz, Winton, and Zephyr. There is little opposition to the landings.

March 6th 1946 X+1
The first troops moving inland encounter the Jap positions, dugin about 2~3 miles behind the beach.
While there are a few concrete bunkers, most are palm logs crisscrossed and covered by sand.
While some units pull back and call for fire support from the ships offshore, the best reponse is from Flamethrowing Shermans.

March 10th 1946 X+4
A few units have broken thru the jap lines and begin heading North

March 12 X+6
First cilivians are encountered in a farmhouse, Dead from Starvation, Several others are described by reporters as worse than Auschwitz.
Allied command begins to lower the expected loss from civilian resistance.

March 15th X+9
Night flights by Star Flare carrying B-29, locates a large force of Jap reinforcements, and wipes it out.

March 17th X+11
First Airstrips on Kyushu recieve B-29's

March 20th X+14
B-29's begin Mass bombing of Hokkaiddo Island from Kyushu.

March 25th X+19
First units reach Northern Line, & begin digging in, [dotted line]
http://upload.wikimedia.org/wikipedia/en/8/89/Operation_Olympic.jpg

March 29 X+23
There are enuff Units along the northern line to ensure no travel between the sectors, some Allied Units turn and begin moving south again hunting any isolated Japanese Units.

April 1st X+30
Allied Command releases the casality reports for Operation Olympic
40.000 killed or missing, and 50.000 wounded.
This was more than MacArthur's 23, but less than Nimitz's 49,000.

April 2nd
B-29 targets are swithed to the Operation Coronet, Area of operations
http://upload.wikimedia.org/wikipedia/en/d/db/Operation_Coronet.jpg
5000 B-29's are targeting every crossroad and village. around Tokyo

April 10th
The smell of charred Flesh is being carried on every breeze

April 15th
The Emperor broadcasts a Surrender.
 
I think that if you have an American invasion of Japan, then you've just sealed the fate of Japan. Once Americans are on the home islands I don't think the emperor is going to be willing to surrender. The war will just go on and on. I think that we'd see the use of poison gas sometime during '46, with the campaign going on until '49 or '50. The many Americans who said Japanese should be spoken "Only in Hell" will get their wish.

I think one of really interesting questions coming out of this is how does the United States respond to what's its just done? I think the general feeling will be that the Japanese basically forced us to do what we did, but by the time the campaign ends the Japanese will probably have lost up to 50% of its population either directly or indirectly to the war. That plus the fact that I think the United States would probably start using poison gas as the campaign bogs down, is going to have some serious impacts on the American pyshe. It'll also really mess with the post-war boom.
 
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