I think you ask the wrong question. (As does Charles: the USSR did not correspond to any idea of a transitional stage: it was a dead end -- but I still want to defend it.)
^^^^^ CB: You should read your own stuff on this type of thing. You are basically saying here that the USSR didn't correspond with your idea of what Marx's transitional stage should look like. But the transitional phase is not an idea or ideal, it is the real movement of things on the ground in the world. That's messy and full of surprises , like you usually say. You should be "surprised" looking back at the USSR.
At anyrate the SU wasn't a dead end; it led to the Chinese rev, the Korean rev, the Viet Namese rev, the Cuban rev, etc. , the Venezuelan radical reforms. These will lead to and be links to the eventual Communist world system
When we get Communism , we will look back and see that the USSR was critical as part of the transition from capitalism to socialism. Communism will be a world system. The transition of the whole world started in Russia. The USSR was critical in bulwarking the Chinese revolution of the transitional phase; it was critical in bulwarking and preserving the Korean, Viet Namese and Cuban revolutions of the transitional phase; even the Yugoslavian rev. China and Viet Nam still declare they are building socialism. I will take their word over protest of Western Utopian Leftists. In other words, it is likely that those in the Communist world system will look back and see all these revolutions as the "seeds" of that Communism that comes into being without any capitalism left, as causal links in the transition. Just by actually existing for so long, the SU demonstrates to future Communists that socialism is viable thereby giving them confidence to pursue their aim.
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The correct question is: Why has the struggle for socialism been so strong and achieved so much under conditions which made _any_ achievement so unlikely?
^^^^^ CB: I don't know about that. Communism isn't inevitable, but socialist achievements are not unlikely. Rather they are probable even if not certain. We must express at least this must cheer leading and confidence for the sake of _esprit de corps_.
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The USSR, the PRC, Cuba were all minor meracles!
^^^^^ CB: No we spin them as expressions of the inherent tendency of history, of capitalism. "Natural" , not super-natural, like miracles. We should follow Marx's example in discussing this.
"But capitalist production begets, with the inexorability of a law of Nature, its own negation. It is the negation of negation." and
"Along with the constantly diminishing number of the magnates of capital, who usurp and monopolize all advantages of this process of transformation, grows the mass of misery, oppression, slavery, degradation, exploitation; but with this too grows the revolt of the working class, a class always increasing in numbers, and disciplined, united, organized by the very mechanism of the process of capitalist production itself. The monopoly of capital becomes a fetter upon the mode of production, which has sprung up and flourished along with, and under it. Centralization of the means of production and socialization of labour at last reach a point where they become incompatible with their capitalist integument. This integument is burst asunder. The knell of capitalist private property sounds. The expropriators are expropriated. "
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Their achievements are the Midnight Special Leadbelly celebrated. They shine a light on us! Instead of endless kvetching re their failure to achieve what was simply not achievable at the time focus on what _we_ have to do now.
Carrol
^^^^^^^ CB: And learn from the successes and failures of the first efforts to build socialism in doing what we have to do now. Past is prologue.