not have any immediate, direct bearing on Japan itself. The Soviets' military target would have been the powerful Japanese army (some two million men strong) in China. This was a formidable opponent, but since the Japanese Navy had effectively ceased to exist, it was effectively cut off from Japan itself. It therefore could not contribute directly to defense of the home islands, whether engaged by the Soviets or not. Contrariwise, even its defeat at Soviet hands would not in itself eliminate -- or even directly reduce -- the potential for a last-ditch desperation defense in Japan, if the Japanese leadership chose that course.
Thus, the fate of Japan's mainland army, and therefore the prospect of a Soviet entry into the war, was for American war planners ultimately a diplomatic prospect rather than a directly military one. Soviet entry into the war might be the final blow that would drive the Japanese leadership to surrender. But if it failed to do so -- and nothing made that outcome certain -- the Americans would still be faced with the prospect of an invasio
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