Problem is that just about any strike on Japanese military bases is going to cause considerable civilian casualties. The Soviets would be faced with a really bad scenario in a conventional war. When the USSR came apart they had several years of monumental supply issues that greatly impacted pilot training and naval ship upkeep (they literally had a couple Sovremenny DDG sink at the quay due to flat out failing to check for leaks), and the Japanese were in very good ship in comparison. Might well be the only way to not lose (which would have taken a sort of fractured situation and turned into 1917 Redux, except with about six sides, all with nukes) would be to go to Special Weapons.
It's like the line about police. Cop can never lose a fight.