Self-described democratic socialist Sen. Bernie Sanders' defense of the policies of the late Cuban dictator Fidel Castro drew swift and widespread condemnation and evoked memories of some of history's bloodiest regimes.

"We're very opposed to the authoritarian nature of Cuba," said Sanders, I-Vt., in a "60 Minutes" interview on Sunday night, "but you know, it's unfair to simply say everything is bad."

"When Fidel Castro came into office, you know what he did? He had a massive literacy program. Is that a bad thing? Even though Fidel Castro did it?" he argued.

In response, Rep. Donna Shalala, D-Fla., who represents a large population of Cuban-born residents in her district, tweeted: "I'm hoping that in the future, Senator Sanders will take time to speak to some of my constituents before he decides to sing the praises of a murderous tyrant like Fidel Castro."

University of Hawaii historian R. J. Rummel, estimated in 1987 that the Castro regime was responsible for the deaths of between 35,000 to 141,000 of its own people. Worldwide, it is estimated that communist regimes have killed an estimated 100 million people.

In Fox Nation's new six-part series, "The Unauthorized History of Socialism," Fox News anchor Bret Baier re-examined the 200-year history of an idea that changed the world, starting from its roots in America in the early 1800's, to its emergence in Europe and the collapse of the Soviet Union, to its apparent rebirth in the United States in 2020.

"By the end of the 20th century, many believed the historic struggle between socialism and capitalism was over," narrated Baier in the Fox Nation series. "You might think the empirical case had been made and the door shut forever on the socialist dream, but you would be wrong."

"Today, socialism is experiencing a revival," said Baier, observing that a disproportionate percentage of Sanders' support, compared to his primary opponents, comes from young voters.

One of Sanders' best-known and most outspoken supporters is freshman Congresswoman Alexandria Ocasio-Cortez D-NY., who provided her own description of the Sanders movement.

"Whether you want to call it democratic-socialism or techno-futurism or like whatever it is," said Ocasio-Cortez during an appearance at the South by Southwest festival in March, "it is because our technological advancement as a society has outpaced our system for handling finite resources because now we are approaching infinite resources."

CLICK HERE TO WATCH EPISODE 1 OF "THE UNAUTHORIZED HISTORY OF SOCIALISM" FOR FREE

"We have created artificial scarcity and that is why we are driven to work 80 hours a week when we are being our most productive at any point in American history," she said. "And so we, you know, we should be working the least amount we've ever worked."

American Enterprise Institute scholar Mark Perry said he sees this latest emergence of socialism as rebranding for a new generation.

"The democratic socialists are repackaging socialism to try to present it to the American people, especially young people," he said, "as some kind of idea that might work if they'd just get the details correct or if they just have the right central planners or the right bureaucrats or the right policymakers or the right politicians."

To watch the entire six-part series, "The Unauthorized History of Socialism" go to Fox Nation and sign up today.

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