WW2: The Composition and Capabilities of the Japanese Military

[seireikhaan]

Well, the Siberian divisions that stopped the Germans at the outskirts of Moscow were pulled from the border with Manchuria. It can be argued that, had the Axis coordinated their efforts better and been able to knock Russia out of the war, Japan would have benefitted from German support.

As CBR said, it could have been disastrous for the Japanese. It may have been worth it to open a second from against Russia, however.

The point, however, is this: when it comes down to it, Russia is simply too big. Let's Japan occupies half of Siberia. And? How does this knock the Soviets out? At this point, Siberia is vast, sparsely populated, industrially desolate, and the winter can kill you. Russia could afford to temporarily fork over large amounts of their eastern lands if it meant having to shift troops to stop the Germans. It would take at least two years of campaigning for the Japanese to put any actual, meaningful pressure on the Soviets. To make the campaign westwards means one of two things: a four month per year campaign through Siberia, whereupon the campaign would have to cease due to inclement weather, or else to trudge through the Gobi desert, which would likely be more disastrous. Simply put, it wouldn't have been possible to be able to apply real and meaningful pressure in time due to the sheer logistical nightmare it would have presented to any invading force.

[Sarmatian]

Soviets intended to use those forces against the Japanese should they attack. Only after spies confirmed Japan won't attack were those forced moved. So, in theory, just by pinning down Siberian divisions Japan could have helped Germany a lot.

Other points still stand, though. Although it may have helped Germany, there would have been little gain for Japan. Maybe if Germans managed to take Moscow in the spring and if Soviet Union capitulated, but that is highly unlikely.