What if Japan declared war on the Soviet Union after Pearl Harbor?

As it turned out, they made absolutely zero progress in that direction after occupying Attu and Kiska. In fact I'm not even sure they made any ATTEMPTS in that direction after occupying Attu and Kiska.
The straits are massive and filled with fog and terrible weather due to the cold artic water mixing with the warm Pacific water. Hard to transit, even harder to find freighters.
 
I agree with all of that, but it's not past the point of delusion for them to think "here comes Tsar Stalin ready to give in". There was perhaps 30-40 or so people who, I even mentioned before that all the go north faction was purged in the 30s but let's indulge the OP.

Only those things you agree with all point against that. On top of all this invading the USSR even if successful doesn't actually get them much except a million square miles of empty. The resources they need to support the war in China are a long way away from them in the USSR and even if they can get to them and they are in intact they have to get them back to where they need them. Those resources are much easier to get going south (and some can only be got going south like rubber).

I'm happy to indulge the OP but you can't just say 'oh they do it', you have to say why they do it because that will effect how they would do it.

The more power is concentrated, the more likely dumb shit happens.

Yes but they also weren't completely stupid to the point where they will ignore the lack of positives and long list of negatives. If you look at most of what we consider the big stupid decisions in WW2 they usually came out of reasonable or at least an internally consistent position based on the perceived context at the time,

That's just the thing, the Japanese observers noted the similarities with their quagmire in China and rightly concluded that the Germans were embellishing their success.
Yes that was my point, for Japan to seriously consider going in, Barbarossa has to go a lot better than OTL.
 
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Only those things you agree with all point against that. On top of all this invading the USSR even if successful doesn't actually get them much except a million square miles of empty. The resources they need to support the war in China are a long way away from them in the USSR and even if they can get to them and they are in intact they have to get them back to where they need them. Those resources are much easier to get going south (and some can only be got going south like rubber).

I'm happy to indulge teh OP but you can't just say 'oh they do it', you have to say why they do it because that will effect how they would do it.



Yes but they also weren't completely stupid to the point where they will ignore the lack of positives and long list of negatives. If you look at most of what we consider the big stupid decisions in WW2 they usually came out of reasonable or at lest internally consistent position based on the perceived context at the time,


Yes that was my point, for Japan to seriously consider going in Barbarossa has to go a lot better than OTL.
And that then means that the Germans probably don't need the Japanese help.
 

Geon

Donor
A few observations.

First - assuming the OP here I agree with those on this thread who say Japan doesn't have the manpower for a full scale war with Russia. They might however have the manpower for a limited attack with the goal of taking Vladivostok. This would mean curtailing some of their southern Pacific operations (i.e. Malaysia or Burma) so that they would have enough manpower for the push or even siphoning off troops from the Chinese theater. This would be a better choice in my opinion because these troops are veterans from several years of warfare and would have a lot more experience.

Second - Assuming an attack on Vladivostok this gives a breather to both Chian-Kai-Shek and Mao who can then marshal their forces for a counteroffensive. If the Burma campaign is cancelled so that a limited offensive to take Vladivostok is possible then the Burma Road stays open, and the West is able to keep pouring supplies into China rather than risking the dangerous air supply bridge over the Himalayas.

Third - This also has ramifications for the Soviet Union. Stalin's spies assured him that Japan was going to move against the United States and Britain. This allowed him to transfer several divisions from Siberia to the West to stop the German onslaught. Without those divisions you definitely will have a battle for Moscow come spring of '42. And it is likely but not certain that Leventry Beria dies during the winter of a "tragic" illness (i.e. lead poisoning).;)

Fourth-The IJN will in the event of the above be pressuring for a final knock-out blow of the U.S.N. hoping that a decisive battle will bring the U.S. to the negotiating table. In this scenario I could see them postponing their Coral Sea operation and instead going for an all or nothing knock-out blow on Midway. This time with six fleet carriers including Shokaku and Zaikuku. The Battle of Midway is a far bloodier affair. How this would end I leave to the naval strategists here.

Finally - Japan has shot its wad with the Russian attack. It is likely that Japan is defeated before the atomic bomb is completed. However the war in Europe will be longer owing to the fact that the Germans are able to penetrate even deeper into Russia and Stalin may not survive as leader if Moscow falls.
 
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If Japan wanted to annoy the soviet union, then maybe they should start with Sakhalin!

While it's true that the soviet forces facing Japanese threats had been weakened, is there any reason to believe that Japanese intel knew this? After all, it seemed to be a surprise to the German army to find a whole new army had come from somewhere.
I ask because it's one thing to open a new front with clear and achievable objectives when you know your enemy is both busy and weakened, but if you think they are just as strong as last time (when you lost) or maybe even stronger that's not going to look like such a good idea.
The OTL decision to allow enemy ( USA) ships to travel unmolested to and from the USSR suggests that they either thought it wasn't safe to attack the USSR or that they thought it wasn't worth it. If the former, they might have a go if not fighting the USA, but if the latter then it's still not worth it unless they can walk in unopposed.
The ships were Soviet flagged not American. If the Japanese know about the Red Army redeployment, they never told the Germans. The Japanese Army had almost no reserves to deal with a Soviet threat at the end of 1941. Going north & south at the same time wasn't a serious option. The Japanese economy was already overstrained in sustaining the war in China, the Pacific War required full mobilization a major land war with the Soviets would be just too much to deal with on top of everything else.
 
My thoughts.

Japan still has to attack the US as it MUST invade south as they need the oil (the whole point if expanding the war beyond China)

The USSR MAY allow US air bases in eastern Russia as they did allow the bases for the shuttle bombing mission and the USSR is going yo be more desperate if Japan is attacking them as well as the fight against Germany.
US air bases in Russia brings with it a much earlier Bombing campaign. And makes the Island hopping campaign not as urgent. It will still happen but it can takes its time. So we may see a bit of a slowdown on that but not a ton.

A good chance Midway never happens as Japan probably does not have the troops to try and invade it. But odds are still good that ultimatly Japan gets ambushed just as baddly as the Uzs was reading Japans personal mail, so to speak.

If Japan does not go south then for all intents and purposes they are screwed by 43 or so as they run out of oil and have yo stop most if not all offensives and conserve for defence. So they will be easier to fight. It will still take a while to end the war unless Japan seas reason. It may take just about as long but it will be easier for the US and GB and the rest as Japan will be mostly stuck in olace waiting yo be attacked whenever the allies decide to attack them.
On the otherhand you have a small chance that Japan surrenders sooner as once the run out of oil they are obviously doomed and whichever faction suggested attacking the USSR and not going south would lose face.

But I just cant see Japan not attacking south. If they dont attack to get oil then why would they bother expanding the war outside China? So i think you will either get a southern attack or no attack at all.

In reality I cant actually see Japan attacking the USSR at all as it gains them nothing of use. And Japan was not that stupid. Keep in mind that Japan knew that they could not beat GB or the US they just thought that the US would not be willing yo pay the cost to win and would sue for peace and that with the US out GB would not be aboe to continue the war as they were still fighting against Germany back home. This was obviously wrong and a total miss-understanding of the US by Japan but it was not strategically/militarily stupid. Attacking the USSR for no reason and or not securing the needed oil would be militarily STUPID.
So i just think this POD more of less impossible. And is the next best thing to the US invading South America in 1942 instead of Affrica.
 
The Russians are going to be bringing their new generation of tanks into the war, the T34 and the KV1. The best Japanese tank is the type 97, which is equivalent to an early model Panzer 3 at best, and totally incapable of damaging a T34. They are going to be facing the same problem the Italians originally did in North Africa, when they had nothing to oppose the Matilda tank, The Russians also have a massive weight of artillery fire the Japanese cannot match, How are the Japanese going to counter this?
 
The Russians are going to be bringing their new generation of tanks into the war, the T34 and the KV1. The best Japanese tank is the type 97, which is equivalent to an early model Panzer 3 at best, and totally incapable of damaging a T34. They are going to be facing the same problem the Italians originally did in North Africa, when they had nothing to oppose the Matilda tank, The Russians also have a massive weight of artillery fire the Japanese cannot match, How are the Japanese going to counter this?
Bushido spirit?

Seriously, what would Japan gain by invading the Soviet Union? There are no strategic resources, just mamba (miles and miles of bugger all). Even if a time traveller told them about the oil reserves it would be no use to them as they need oil now, not in 20 years time. Yes it might help the Germans, but why should Japanese soldiers die just to benefit Hitler?
 
The Russians are going to be bringing their new generation of tanks into the war, the T34 and the KV1. The best Japanese tank is the type 97, which is equivalent to an early model Panzer 3 at best, and totally incapable of damaging a T34. They are going to be facing the same problem the Italians originally did in North Africa, when they had nothing to oppose the Matilda tank, The Russians also have a massive weight of artillery fire the Japanese cannot match, How are the Japanese going to counter this?
BTs and T26 already outclassed most Japanese tanks so they didn't really need the T34 [1]. They had actual armour (though not impenetrable) and the 45mm (and the 37 of any surviving BT2) was easily capable of dealing with any Japanese tank.

Perhaps this would have been the ideal combat environment for the T50, which was basically a small T34 with 45mm gun.

[1] I'll agree that the terror factor of the T34 or KV1 being proof to all their weapons would have been a very useful bonus.
 
Les BT et les T26 surclassaient déjà la plupart des chars japonais, ils n’avaient donc pas vraiment besoin du T34 [1]. Ils avaient un blindage réel (mais pas impénétrable) et le 45 mm (et le 37 de tous les BT2 survivants) était facilement capable de faire face à n’importe quel char japonais.

Peut-être que cela aurait été l’environnement de combat idéal pour le T50, qui était essentiellement un petit T34 avec un canon de 45 mm.
What about the Tiger ? OTL the japanese wanted to purchase a Tiger tank. Could something like this happen on a larger scale (like a whole division) TTL ? Or they could even produce it (if this is possible).
 
What about the Tiger ? OTL the japanese wanted to purchase a Tiger tank. Could something like this happen on a larger scale (like a whole division) TTL ? Or they could even produce it (if this is possible).
They would have been far better off purchasing and license producing Panzer III and IV. Those are still capable of operating in the terrain of Asia and the Pacific. The 'big cats'... not so much.
 

nbcman

Donor
What about the Tiger ? OTL the japanese wanted to purchase a Tiger tank. Could something like this happen on a larger scale (like a whole division) TTL ? Or they could even produce it (if this is possible).
Considering the first Tiger I tanks weren't produced until August 1942, there's a whole bunch of enemy territory / enemy controlled sea lanes between Nazi Germany and Imperial Japan to try to ship a whole division's worth of tanks. Note that the Germans never had such a large organization as they used them in company / battalion organizations, not divisions. According to Wiki, the Japanese did purchase a Tiger I in 1943 but it was not delivered. https://en.wikipedia.org/wiki/Tiger...began in August 1942 at,1944 at 104 per month.
In 1943, Japan bought several specimens of German tank designs for study. A single Tiger I was apparently purchased, along with a Panther and two Panzer IIIs, but only the Panzer IIIs were actually delivered.[54] The undelivered Tiger was loaned to the German Wehrmacht by the Japanese government.
 
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