The Road to War between the U.S. and Japan was Paved by Irreconcilable Worldviews

[ellisonz]

2. My best guess is that after Pearl Harbor...

...whatever worries Stalin had about the Japanese were alleviated by our massive aid effort to Nationalist China and our engagement in the South Pacific.

http://en.wikipedia.org/wiki/Soviet-Japanese_Border_War_%281939%29
http://en.wikipedia.org/wiki/Soviet%E2%80%93Japanese_Neutrality_Pact

Hitler was a far greater threat to the Motherland than the Japanese could have ever posed. The Far East for Russia was always kinda of a diplomatic and military backwater compared to the Western Front and Central Asia. I would guess there was no hard agreement, and even if there was, it would have cost Japan very little to ignore it since Germany was not crucial to the Japanese war effort.

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