Actually communism has never existed. The Soviet Union wasnt Communist, it was a socialist totalitarian oligarchy, just as China & Vietnam are now (although the socialism is mainy symbolic in thos countries now).
BTW, the Russian revolution wasn't in support of communism. The Menshovics were the ones who won the revolution & deposed the Czar's autocracy. They were basically for a constitutional monarchy along the social democratic model of Western Europe. But then the Bolshavics held a coup & hi-jacked the revolution & had the Czar's family executed, thus causing the Russian Civil War to start. 
The fact is if they had a election in 1917 the Menshovics would had won by a country mile. But the Bolshies were cleverer that's all. Lenin was in fact a paid up member of the of the Kaiser's secret service, so once he was in power he had Russia surrender to the Kaiser the grand Duchy of Warsaw, the Grand Duchy of Finland, the Duchy of Kureland & the rest of the Baltic states & much of the Ukraine & White Russia. Consequently when Germany signed the armistice, those regions had no overlords & were free. The new state of Poland ended up with those parts of the Ukraine & White Ruusia that Lenin had signed over to the Kaiser. Later Trotsky won the civil war & then invaded Poland to get those territories back, the Pols won & gained even more land. However Stalin got all that back (Polish Belarus & the Polish Ukraine) during WWII. Poland was given a little bit of Germany as compo.
Anyway in a mixed economy both socialism & capitalism has its place. Once one restricts itself to a certain ideaology they are fuked. Policies from both the left & the right should be utilised, depending on what's right for the job at hand. That's the strength of the many OECD nations, which are all mixed economies. For example the main reason for Japan's success during the 50's, 60's, 70's & 80's were that all its corporations were controlled by the bureaucrats of the Industry ministry who decided that electronics was the way to go (Sony didn't get involved in electronics because it wanted to, it got involved in electronics because the Industry Ministry told them to). Its no coincidence that the nations that most closely follow capitalist ideals are in the 3rd world, where most people are dirt poor.