What would be the effects of a war between Communist China and the USSR during the Cold War? I think a short spit (a la the Sino-Indian War or the Sino-Vietnamese War) would be the most possible, but it would of course require a deeper and much more vigorous Sino-Soviet Split.
PODs aside, what would have happened? Where would the major fighting have taken place, and who would have been the most victorious? How would this have affected Cold War politics, and how would the West and NATO have viewed such a conflict?