What Do Over-the-Hill Rockers Have in Common with Socialist Regimes?

In their early stages, socialist experiments are usually glorified by Western intellectuals. The Soviet Union and Maoist China certainly were; on a smaller scale, so was North Korea, and more recently, so was Venezuela. But sooner or later, those experiments always become an embarrassment for their Western supporters, who then retroactively disown them ("that wasn't real socialism!").