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sparten
13 Jul 05,, 12:30
I was wondering how the planned invasion of Japan in November 1945 would have panned out.?

Assuming that in our senario, the Atomic Option does not exist, the following would have happened.

The Allied Navies were already mostly in the Pacific area since 1944. In addition, the Brits would have their new Colosses Class Carriers, the Americans would have the Carriers historically not deployed e.g USS Antietam, and the New Midway Class Battle Carriers. THe RCN, RAN and RNZNN (if that is right) would also be on station

The IJN at this point was more or less history, so it would not have made much of an impact.

At the time of the historical surrender, Allied Airforces were redeploying to Okinawa. So in addition to the Superfortresses, you have B-17s and Lancasters from Europe. These would have supported the Invasion itself, in addition to normal bombardment missions.

Finally you have land forces redeploying from ETO, as a well as from the Eastern Front.

Presuming the actual invasion plan Operation Downfall, was being followed, how long do you think it would have taken for the Allies. How would hings have gone in other theaters [MAnchuria and Burma].

Remember, in this universe the Atomic option does not exist?

Officer of Engineers
13 Jul 05,, 14:09
Lemay was ready to firebomb Japan back to the stoneage. Considering most houses were paper and wood - not that hard to do.

Shek
13 Jul 05,, 14:52
To understand the worst case scenario of casualties for the invasion of Japan, DOD didn't have to order any new Purple Hearts until 2000, and that was only to replenish depot level stocks.

http://hnn.us/articles/1801.html

sparten
13 Jul 05,, 15:48
Lemay was ready to firebomb Japan back to the stoneage. Considering most houses were paper and wood - not that hard to do.

Fine, sir, but how would the invasion itself have gone. My own reading has been that Japanese Resistance would have been fanatical, but would it have been effective?

What about SE Asia,China, where the IJA still had a presence. What about that battle.

Amled
13 Jul 05,, 16:28
What about SE Asia,China, where the IJA still had a presence. What about that battle.
The million+ man army Stalin had mobilized in the east should have been able to eliminate their presence in China and Manchuria.
As for SE Asia, the Allies were already rolling them back up to and including Burma.

sparten
13 Jul 05,, 18:01
Actually they had already taken Burma. Many Indian divisions for example had relocated to Okinawa in preparation for invasion.

How would the invasion itself have gone? I have always thought the Japnese would probably have been defeated fairly quickly. Just look at the firepower.

American Army in Europe, US Marines, Pacific Army.
Soviets
British Army, and IMHO the best fighters of all the, Indian Army.
Canadians, Aussies and the rest.

The Allied Airforces, B-17,B-24, Lancasters, Stirlings in addition to B-29.

Almost 50 fleet carriers.

Japan was history, at least IMO

Bill
13 Jul 05,, 18:15
It would've been a bloodbath(and technically, there were two invasions, the first on honshu, the second on Kyushu.) The Japanese had correctly guessed where the allies were to come ashore, and they had by far the greatest network of defenses ever faced waiting to meet us from the moment we landed.

Figure 12-18 months start to finish, with well in excess of 1,000,000 US/Allied casualties, and as many as 20,000,000 japanese.

sparten
13 Jul 05,, 20:13
It would've been a bloodbath(and technically, there were two invasions, the first on honshu, the second on Kyushu.) The Japanese had correctly guessed where the allies were to come ashore, and they had by far the greatest network of defenses ever faced waiting to meet us from the moment we landed.

Figure 12-18 months start to finish, with well in excess of 1,000,000 US/Allied casualties, and as many as 20,000,000 japanese.

No airforce, no navy, fanatical resistance, yes, effective no.

troung
13 Jul 05,, 20:48
They still had an air force up to the end of the war...

Wraith601
14 Jul 05,, 05:12
No airforce, no navy, fanatical resistance, yes, effective no.

The Japanese still have lare numbers of kamikazes including the Ohka rocket plane hidden throughout the countryside. Lots of them would have gotten up and some would have made it through. It would have been an extremely bloody battle. Anybody know if this was ever novelized or anything?

sparten
14 Jul 05,, 06:03
The Japanese were ready to surrender in July1945. Am invasion would have succeeded within a few days.

Reason shortage of raw materials, no oil hence no avaition fuel.

Shek
14 Jul 05,, 11:55
They still had an air force up to the end of the war...

They had an air force, but little to no trained pilots and a fast dwindling supply of fuel.

Officer of Engineers
14 Jul 05,, 12:22
The terrain was a great equalizer for the Japanese which forced the Americans to fight a WWI style of combat. However, as the Soviets had shown initially in Siberia against an IJA incursion and then, wiping out the IJA mainforce in Manchuria, when it came to modern mechanized manouver warfare, the Japanese were nothing but speed bumps to be stomped.

sparten
14 Jul 05,, 13:38
Pardon my ignorance, but how is the terrain in Japan?

FlyingCaddy
16 Jul 05,, 07:29
First, I would like to make a few notices. The operations would have been Kyushu first, then Honshu (b/c the latter is the main island) Second the names of both assualts were Olympia for the former and Coronet for the latter.

Now Japan is a very mountainous country, so although in mech warfare the Russians and even the western allies could probably out maneuver them on flat terrain, how would their mechanized tactics face up to an enemy using most of its mountains as forts.

Further we need to remember that the early model B-36s would start to come on line just as the invasion occured, so it is possible that even attacks from state Side could occur.

Bill
16 Jul 05,, 09:01
"The Japanese were ready to surrender in July1945. Am invasion would have succeeded within a few days."

Your delusion notwithstanding, that is anything but the case.

Since when is 6,000 plus aircraft 'no airforce'?

Bill
16 Jul 05,, 09:02
The B-36 first entered service in 1947.

You're probably thinking of the B-32 Dominator.

Stone Cold
16 Jul 05,, 10:26
First, I would like to make a few notices. The operations would have been Kyushu first, then Honshu (b/c the latter is the main island) Second the names of both assualts were Olympia for the former and Coronet for the latter.

Now Japan is a very mountainous country, so although in mech warfare the Russians and even the western allies could probably out maneuver them on flat terrain, how would their mechanized tactics face up to an enemy using most of its mountains as forts.

Further we need to remember that the early model B-36s would start to come on line just as the invasion occured, so it is possible that even attacks from state Side could occur.

Is that a Nazi as your avatar?

sparten
16 Jul 05,, 13:05
"The Japanese were ready to surrender in July1945. Am invasion would have succeeded within a few days."

Your delusion notwithstanding, that is anything but the case.

Since when is 6,000 plus aircraft 'no airforce'?

No airforce when they mostly cannnot fly due to lack of spare parts and fuel. Not to mention pilots.

Japan was defeated, this was the opinion of almost all senior Allied Officers. I have always read your posts with the utmost of repect, but in this case I think I will go with the Generals, (reluctantly).

The invasion was simply going to be the coup de grace. Hell, the blocade on its own might well have succeded, in starving them out. Even Boshido has its limits.

Wraith601
17 Jul 05,, 07:42
No airforce when they mostly cannnot fly due to lack of spare parts and fuel. Not to mention pilots.

Japan was defeated, this was the opinion of almost all senior Allied Officers. I have always read your posts with the utmost of repect, but in this case I think I will go with the Generals, (reluctantly).

The invasion was simply going to be the coup de grace. Hell, the blocade on its own might well have succeded, in starving them out. Even Boshido has its limits.

Then why did the Operation Downfall planners project Allied losses exceeding 1 million in some cases? One draft I've seen expected the ENTIRE 1st Marine Division to be wiped out on the first day of the invasion. Stop making stuff up to support your incorrect viewpoints.

leib10
17 Jul 05,, 08:04
Is that a Nazi as your avatar?

That's Feldmarschall Erwin Rommel, and no, he was not a Nazi. In fact, he was executed for supposedly taking part in the July 20 assasination attempt on Adolf Hitler.

Anyway, in the end, the big one came cheaper in terms of loss of life. An invasion of Japan would've added millions more killed to the bloodiest war in history.

sparten
17 Jul 05,, 13:17
on. Stop making stuff up to support your incorrect viewpoints.

US Strategic Boming Suurvey,
After interviewing hundreds of Japanese civilian and military leaders after Japan surrendered, reported:
"Based on a detailed investigation of all the facts, and supported by the testimony of the surviving Japanese leaders involved, it is the Survey's opinion that certainly prior to 31 December 1945, and in all probability prior to 1 November 1945, Japan would have surrendered even if the atomic bombs had not been dropped, even if Russia had not entered the war, and even if no invasion had been planned or contemplated

http://www.ibiblio.org/hyperwar/AAF/USSBS-PTO-Summary.html#tioabotr

if you can give reasons and references to support your claims, I would be delighed to read them.

FlyingCaddy
17 Jul 05,, 17:03
The B-36 first entered service in 1947.

You're probably thinking of the B-32 Dominator.
I stand corrected, I dont think the B-32 would have made too much of a difference it was merely an alternative to the B-29 so yeah my comment was quite facetious.

TopHatter
17 Jul 05,, 17:11
That's Feldmarschall Erwin Rommel, and no, he was not a Nazi.

If you just glance at that picture, it looks just a bit like Ike :redface:



In fact, he was executed for supposedly taking part in the July 20 assasination attempt on Adolf Hitler. .

I thought he committed suicide because of the plot.....which amounts to the same thing I guess. Allowed to commit suicide is probably more like it :frown:

FlyingCaddy
17 Jul 05,, 17:19
That's Feldmarschall Erwin Rommel, and no, he was not a Nazi. In fact, he was executed for supposedly taking part in the July 20 assasination attempt on Adolf Hitler.

Anyway, in the end, the big one came cheaper in terms of loss of life. An invasion of Japan would've added millions more killed to the bloodiest war in history.
Actually thats Gerneal Heinz Guderian, the best German general not to attain Field Marshal, because Hitler was a jealous prick.

TopHatter
17 Jul 05,, 17:21
Actually thats Gerneal Heinz Guderian, the best German general not to attain Field Marshal, because Hitler was a jealous prick.

Dang! That's what I thought.

My neighbor has a German Shepard that her often-absent husband named "Rommel". Whenever I was over at her house, I would delight in annoying her by calling him "Guderian" :biggrin:

leib10
17 Jul 05,, 17:40
Wow, I could've sworn that was Rommel. And yes, he was given a choice of standing trial in public or taking his own life. He chose the latter, and was given a public state funeral with no attention at all given to his treachery.

And I knew a guy who named his German Shepherd "Blondie", which was the name of Adolf Hitler's German Shepherd.

Wraith601
18 Jul 05,, 20:55
US Strategic Boming Suurvey,
After interviewing hundreds of Japanese civilian and military leaders after Japan surrendered, reported:
"Based on a detailed investigation of all the facts, and supported by the testimony of the surviving Japanese leaders involved, it is the Survey's opinion that certainly prior to 31 December 1945, and in all probability prior to 1 November 1945, Japan would have surrendered even if the atomic bombs had not been dropped, even if Russia had not entered the war, and even if no invasion had been planned or contemplated

http://www.ibiblio.org/hyperwar/AAF/USSBS-PTO-Summary.html#tioabotr

if you can give reasons and references to support your claims, I would be delighed to read them.

Operation Downfall (http://en.wikipedia.org/wiki/Operation_Downfall)

The Allies might have brough the Japanese to their knees via more aerial bombing without nukes, but it would have been a bloodbath either way.

Bill
18 Jul 05,, 21:32
The Japanese Defenses

At the time of the start to planning of Olympic, there were 1-1/2 divisions based on southern Kyushu; these with various service bases there amounted to about 45,000 men. Planners expected an additional three divisions to be moved into the area by the time of the landings. The Japanese were able to predict the landing using the same logic as US planners and moved 9 more divisions into the area for 216,000 men by the time of the surrender. Each side of the central bay had an army, each was divided into two functions - a static defense force on the beaches to fight to the death while allowing reinforcements to arrive, and the mobile reserve to push the American back into the sea. The three logical landing beaches were defended from the shore to the nearby mountains with new troops. The reserves located in the mountains were experienced troops from Manchuria with light tanks. Supporting the troops were the remnants of the navy and air force, lightly armed volunteers, and an array of "special" weapons.

The air forces contained 5,600 conventional combat planes and a similar number of older planes and trainers as Kamikazes. The combat planes were withdrawn from Kyushu and the Kamikazes moved in. Japan was so short on aircraft and fuel that B-29s and carrier task forces were not routinely attacked so as to conserve combat aircraft for the final battle. Equal numbers were assigned to Kyushu and Tokyo areas. As the date for the first battle approached, more were moved to Kyushu with the Tokyo forces to be replaced with promised new production.

Kamikaze tactics were initiated in the Philippines and became a doctrine that inflicted terrible damage to warships off Okinawa. The invasion of Kyushu would see the distance reduced, flying over familiar land instead of over-water navigation, and with targeting changed from warships to troop ships, the plan was to inflict intolerable damage to the invasion force before it hit the beach.
The following "special weapons" were established on southern Kyushu.

* Kamikazes -- 2,100 army planes and 2,700 navy planes.
* Baku - suicide missile carried by a bomber.
* Mini-subs, each with 2 torpedoes, 500 were building.
* Fleet submarines -- arm the 57 remaining that had been dedicated to resupply of outposts.
* Kaiten - suicide torpedoes with a 20 mile range.
* Shinyo - suicide motorboats. The army had 1-man, 17 foot motorboats. The navy had 2-man, 22 foot boats.
* The largest surviving warships were destroyers that were prepared for suicidal attack on the invasion convoys.
* On the land, human mines in which soldiers had explosives strapped to their bodies and were to crawl under a tank. Other explosives were packed with a suction cup to be attached to the side of a tank. And shaped charges on a long pole were to be detonated on the side of a tank.
* Paratroopers were to attack Okinawa to disrupt flight operations during the invasion period.


Alternatives to Olympic.

Rather than invade Japan, the country could have been blockaded with a ring around the Yellow Sea from Shanghai to Korea. This was not assured to cause the surrender of Japan. The direction of the war would have been towards reinforcing China and supplying the Soviet Union for their movement of troops into Manchuria, Korea, and mainland China.

A plan resurrected after the enemy buildup on Kyushu exceeded all expectations, was the occupation of the less well defended northern island of Hokkaido and northern part of Honshu. This would have been of equal distance from Tokyo, but further from American army, naval, and air force centers. Shipping was already a problem with large numbers unreleased from the Atlantic needed to supply Europe and return troops to the US, to redeploy air and service forces from Europe to the Pacific, to supply the Pacific buildup and to move several corps to the invasion sites. Every tanker in the US fleet was required to provide the millions of gallons of fuel required by the ships involved in the Kyushu operation. More fuel and shipping would be required to move 1,100 miles further away to the north.

Casualties.

There are two sets of potential casualty figures; a low number used to gain approval to proceed with the operation; and a high number used to plan reserve forces, medical needs and, as it turned out, to claim as lives saved by use of the atom bomb. These figures changed over time, starting low and going higher as the enemy build up on Kyushu was discovered.
The low casualty figures were based on the landings at Okinawa, Lingayen Gulf, and Normandy. Okinawa and Lingayen Gulf were undefended on the beaches, the fighting took place in the mountains where each Japanese caused one US wounded and 20% caused US deaths. Normandy had the same three-beach landing pattern, but two beaches were relatively easy, only the landing at "bloody" Omaha was vigorously defended. All three Kyushu beaches were defended in depth, to the death.

It would have been more realistic to triple the rate of Omaha beach rather than take the average of the three Normandy beaches as the planners did. There was also a difference in scale. Normandy landed 5 divisions plus 3 airborne divisions. Olympic was to land 14 divisions. Coronet was to have 23 divisions.

The defended beach at Tarawa was a shock to Marines landing, with unexpected losses.
The US invasion tactic was then changed from surprise to heavy bombardment. The Japanese had changed their defensive positions in the later Pacific actions from defense of the beach to the mountains. Kyushu was to have both forms of defense: well prepared installations near the beaches and well prepared caves in the mountains.
The US planners expected that radar would detect Kamikazes coming through the mountains, carrier fighters would be vectored to intercept them, and proximity-fused ship's anti-aircraft fire would take out any that got through. However, 250 highly maneuverable warships were hit a few months earlier at Okinawa with these same defenses, in open water; the prospects of loaded troop ships taking casualties was high and each hit could take half-a-thousand lives. Whereas two Messerschmitts were able to attack troops on the Normandy beaches, 5,000 Kamikaze were aimed at the approaching troop ships while still at sea. It would be reasonable to increase the hit rate of Kamikazes from nearby bases, yet the planners reduced it. Japanese planners expected almost 500 ships would be sunk during the landing. US planners expected 15-20% losses, they had no experience with such attacks on merchant ships at sea.

Good weather was required for close air support on the cloudy islands of Japan. A typhoon had once saved Kyushu from invasion by Mongols in 1281. A storm that forced the carriers to withdraw or even to cause the 2,000 planes to remain on deck, would take away an important part of the invasion support. A storm would also hamper getting supplies over the beaches to the armies.
The original plan was for 9 divisions to attack 3 divisions of defenders. As enemy reinforcements were observed, the size of the invasion force was increased. The final plan had 18 U.S. divisions attacking 11 IJA divisions in defensive positions. Most sources give the advantage to defenders by 3:1, that is, attackers must outnumber defenders by three to be sure of victory.

Casualty figures were a guess that changed with time. There are sufficient numbers available to support any post-war position that any author chooses to take. Low numbers are quoted as reasons to do the invasion, 125,000 for Olympic and to end the war. High numbers, one million US casualties for Downfall, are quoted to justify the A-bomb and end the war. Typically, 25% of casualties are deaths. On average, 5 Japanese soldiers died for each American death.
Japanese casualties were not subjected to planning. If all troops resisted to the death, then the typical survival rate would have only included injured and unconscious soldiers. 216,627 troops were surrendered on Kyushu alone -- more than were expected -- and this was two months before the planned invasion. Civilian casualties are a real unknown. 97,000 were killed in the bombing of Tokyo on March 9; the numbers from land warfare would also be high. Consider ratios of any proportion you desire. Civilian losses in some European cities were considerable; certainly Japanese casualties would be in the multiple millions.

CORONET

Coronet was the attack across the Kanto plain to capture Tokyo. The broad plan was still going through refinement.
Naval bombardment by guns and air would begin at Y-15. There would be two simultaneous assaults on Y day.
First Army was to land on the southern half of Kujukuri Beach with 4 divisions to secure a beachhead. On Y+5, with two more divisions landed, they would move across the peninsula to clear the east side of Tokyo Bay and move north to take the port city of Choshi. Service troops would built land based air bases under the cover of carrier aircraft. Thirty air groups were expected to be in place by Y+30.
Simultaneously, Eighth Army would land at Sagami Bay with four divisions to establish a beachhead, secure the Miura Peninsula and Yokosuka naval base. At Y+10, two armored divisions would land and move straight north to establish a blocking position north of Tokyo. Other elements were tasked to take the port cities of Yokohama and Kawasaki to provide supply points for the troops.
First Army was to attack across the Kanto plain to Tokyo about Y+30 with Eighth Army tanks ready to provide assistance. Tokyo had already been extensively destroyed by bombing.
Coronet was a larger operation than Olympic, but the landing on Kyushu, the southern island, was expected to be the more expensive because all of the homeland defensives would have been expended there and the promised replacements for Coronet would have been made industrially impossible. Air Force would be flying from a hundred airfields on Kyushu. A 100 carriers could have been available including new construction and those coming from the Atlantic.
The Joint Chiefs expected the Japanese to surrender after exhausting themselves in Operation Olympic. Thus Coronet would not be required.
However, if necessary, follow up operations after Tokyo would have been initiated in the south, central, and north of Japan with US troops from Europe who had taken leave in the US -- only Air Force, air field construction, and service units had gone from Europe directly to the Pacific. And troops from Allied countries would be available.

http://www.ww2pacific.com/downfall.html

Praxus
18 Jul 05,, 21:51
That's Feldmarschall Erwin Rommel, and no, he was not a Nazi. In fact, he was executed for supposedly taking part in the July 20 assasination attempt on Adolf Hitler.

Anyway, in the end, the big one came cheaper in terms of loss of life. An invasion of Japan would've added millions more killed to the bloodiest war in history.

Erwin Rommel commited suicide when he learned that hitler killed himself. Are you sure you aren't thinking of someone else?

Bill
18 Jul 05,, 22:10
"Erwin Rommel commited suicide when he learned that hitler killed himself."

Say what?

Major Dad
18 Jul 05,, 22:28
[QUOTE=sparten]The Japanese were ready to surrender in July1945.

The Japanese civilian government may well have been ready to surrender, unfortunately, they had absolutely no authority over any aspect of the war. That was the exclusive prerogative of the Imperial General Staff. And they were most assuredly not ready to surrender. The abortive attempt, by fanatical Army officers, to “save the Emperor from himself” by destroying the recordings of his speech announcing the surrender is proof of that.

As for how effective the Japanese resistance would have been, I think any account of the invasions of Iwo Jima or Okinawa would be enlightening. I recommend “The Rising Sun” by John Toland.

brownboi4eva
18 Jul 05,, 22:30
FIeld Marshall Ervin Rommel commited suicide....The saboteurs in the assasination plot wanted to make Rommel the leader of Germany after Hitlers assasination--he was asked about it but he said he didnt want any part of it and his job is just leading his troops but he didnt inform SS or anyone about the plan-- . After the attempt failed Hitler found out and sent the SS to his house, he had 2 choices - The pill or a public trial that would strip his family of any honor and he'd get the death penalty anyways. So he sat in the SS car and popped the pill.

Bill
18 Jul 05,, 23:01
Major dad: Agreed on all counts.

Praxus
19 Jul 05,, 00:05
"Erwin Rommel commited suicide when he learned that hitler killed himself."

Say what?

My mistake, he was forced to commit suicide.

Leader
19 Jul 05,, 00:26
My mistake, he was forced to commit suicide.

...because he was involved in trying to kill Hitler. The Nazi's tried to cover it up during the war.

leib10
19 Jul 05,, 00:59
I believed they said that he died of the wounds he received when he was strafed by a plane (which really did happen).