Fidel Castro is still a radioactive person to have any association with, despite the fact he is no longer in politics and has one foot on the grave and the other on a banana peel. His brother Raul is still around, though, to remind people.
It is a good thing that clip came out now and not used in the fall campaign against him if he had gotten the nomination.
Not unlike the time that Donald Trump hesitated to “disavow” David Duke while his opponents call him racist, Sanders failed to distance himself sharply from Fidel Castro while his critics call him a communist. No worse a place could he have lobbed the flub than in South Florida, in Miami, about a five-minute walk from Freedom Tower, the Ellis Island of Cubans fleeing the Castro regime.
It might not have been a fair question -- the Florida equivalent of comparing yourself to Hitler -- but it could have been easily and directly answered. Hillary Clinton seized on Sander’s blunder a few seconds later.
“I just want to add one thing to the question you were asking Senator Sanders,” she said, after a short response to a question about Puerto Rico. “I think in that same interview, he praised what he called the revolution of values in Cuba and talked about how people were working for the common good, not for themselves. I just couldn't disagree more. You know, if the values are that you oppress people, you disappear people, you imprison people or even kill people for expressing their opinions, for expressing freedom of speech, that is not the kind of revolution of values that I ever want to see anywhere.”
The term "communist" was becoming obsolete, but now threatens to make a comeback thinks to this monumental screw-up by Sanders.
This earlier article goes into more detail about Sanders and why he can't be the Democratic Party nominee:
A weird palette of questions, sure, but when Sanders was mayor of Burlington, he answered “yes” to all of them. Hidden on spools of microfilm, buried in muffled and grainy videos of press conferences and public appearances, Mayor Sanders enumerated detailed—and radical—foreign-policy positions and explained his brand of socialism. (If you find foreign-policy debates tedious, feel free to ask Sanders if he still believes that “the basic truth of politics is primarily class struggle”; that “democracy means public ownership of the major means of production”; or that “both the Democratic and Republican parties represent the ruling class.”)
In the 1980s, any Bernie Sanders event or interview inevitably wended toward a denunciation of Washington’s Central America policy, typically punctuated with a full-throated defense of the dictatorship in Nicaragua. As one sympathetic biographer wrote in 1991, Sanders “probably has done more than any other elected politician in the country to actively support the Sandinistas and their revolution.” Reflecting on a Potemkin tour of revolutionary Nicaragua he took in 1985, Sanders marveled that he was, “believe it or not, the highest ranking American official” to attend a parade celebrating the Sandinista seizure of power.