Well I'm following your logic, but I think there would be a serious constraint on Japanese effective operational area concerning the Russians. It all comes down to available weapons systems at the time. With the basic small arms comparisons PPsH 41, Svt40 versus the Arisaka. The Japanese type 96 was similar to the Bren and based on the Czech ZB26 used by the Waffen SS. but other than the Nambu type 11, Hotchkiss copy the Japanese lacked SAWs. As far as Armor the Japanese were no match for the Russians tank for tank as well as AT weps. The Navy conflict easily goes to Japan but then there's operational distance in play which could be compensated somewhat by Japanese Air Power but that's if they secured land bases to further the operational effectiveness. That operational distance would be key and how much territory would Russia give up undefended if Germany was a greater threat? Thought the Nationalist anti communist treaty made sense especially since Germany had provided equipment to China under license.

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