The answer is quite complex, and was first outlined (to my knowledge) by Kristian Niemietz of the Institute of Economic Affairs in his book Socialism: The Failed Idea that Never Dies. As he says, “Today, holding the failures of … the former Soviet Union against a contemporary socialist is considered crass and boorish.” He demonstrates that the application of socialist ideals in a nation enters into a demonstrable and repeated cycle.
First, every pro-socialism commentator and quite a few neutral ones hail the institution of the new socialist commonwealth. They say that the new dawn is here, and the realization of socialist ideals and principles is being put into practice at last.
Next, the internal contradictions of socialism mean that the wheels start to come off the economy. There are shortages, or civil unrest, or the realization by a class of citizens that they are worse off than under the old regime and start to push back. The commentators say that this cannot be the fault of socialism and start to blame “wreckers” or “saboteurs” or foreign agents. This is where I suspect Venezuela is at the moment, with any good socialist saying that Venezuela would be doing well were it not for economic sanctions or the CIA. It is also what led to the Cultural Revolution in China.
Finally, when everything has gone to heck in a handbasket, when the economy has collapsed, and, in the worst cases, large numbers lie dead, the very same commentators who proclaimed the dawn of real socialism will say that the state failed because it was never real socialism in the first place. The emergence of a dictator, for example, will be taken as prima facie evidence that the system was never socialist at all, despite the very same commentators previously proclaiming that dictator the champion of the working man.
Thus, if every example of real socialism having been tried is not real socialism, socialism gets a get out of jail free card. The idea that socialism contains internal contradictions that doom it is simply not countenanced.
This leads to the phenomenon that when self-proclaimed “democratic socialists” like Rep. Alexandra Ocasio-Cortez say, “[W]hen millennials talk about concepts like democratic socialism, we’re not talking about these kinds of ‘Red Scare’ boogeyman. … We’re talking about countries and systems that already exist that have already been proven to be successful in the modern world,” they are pointing to systems that actually aren’t socialist at all. That will be the subject of my next blog post about socialism.