Alright, so let's say that the USSR reformed at some point between 1935-1970 into a democracy, not just politically, but actually instituted worker's democracy to the full extent and generally respected civil liberties, with the exception of 'dealing' with extremists, like militant capitalists.
How would this change the world, would it allow the USSR and West to become closer, would the USSR still be around today, and if not, how would a period of atleast twenty years of democratic rule affect the post-soviet republics?