Come along with me on a little thought experiment. Imagine that, horrified by the creeping authoritarianism in Donald Trump’s America, you decided you could take no more and you moved to New Zealand, say, for a fresh start.

Now imagine that, as an immigrant to New Zealand, you saw a radical right-wing politician rise to national prominence. Naturally, some enterprising local journalist would eventually ask that politico about his views on President Trump. Now imagine the response sounded something like, “Well, while we certainly wouldn’t want Donald Trump’s divisiveness and authoritarianism here in New Zealand, it is a fact that he presided over the greatest economy in U.S. history and he certainly made America great again.”

This, I suspect, would drive you crazy. And it would drive you crazy for a good reason: not so much because it’s wrong, specifically, but because it’s propaganda.

Like all good propaganda, our New Zealand politician’s response blends a pinch of truth (the unemployment rate really is very low and the stock market has performed very well) with a willful ignorance of history (the economy was doing well long before Trump reached power) and a determined effort to obscure a deeper, much more pernicious dynamic (no amount of economic health is worth sacrificing the basics of democracy and the separation of powers).

Hearing it, you’d instantly see as hollow the politician’s assertion that he didn’t want Trumpian divisiveness in his country. How could you trust a person so ready to swallow and repeat a propaganda whopper like that?

If you can imagine your reaction to this right-winger, you can begin to glimpse the enormous concern Venezuelans and Cubans feel when we hear Bernie Sanders praise Fidel Castro’s education system.

The first thing to grasp is that Cuba’s global reputation for having an excellent education system isn’t a result of the quality of its education system. As scholars have long known, Cuba’s overall educational performance is middling for the region: roughly similar to that of many other Latin American countries that brought their literacy rates from round-about 75 percent in the 1950s to not-far-from 100 percent today.

Yes, Cuba made education available free to everyone through the university level. But so did countries such as Argentina, Ecuador, Uruguay and Mexico. There was never any need to build a police state to bring people to school — an insight so obvious, it’s ludicrous to even have to write it.

In reality, Cuba’s reputation for educational prowess is mostly a product of a relentless, multi-decade propaganda campaign. Virtually every speech by every Cuban diplomat and regime admirer for the past seven decades has made a point of praising Cuba’s supposed literacy miracle. Cubans who have left know the propaganda only too well, and understand why a government desperate to establish its legitimacy in the face of the mass impoverishment of its population would turn to it again and again.

To Cubans and Venezuelans — who have witnessed much the same kind of propaganda — talk of Cuban educational prowess grates not because it’s wrong, exactly, but because it serves as a simple way to identify who’s ready to be duped by regime apologists. We know propaganda doesn’t need to be entirely false to be profoundly damaging. So we despair when we hear it parroted by those who ought to know better.

The bottom line is that when you associate yourself with an ideology whose past contains some of history’s worst crimes, you take on a special duty to denounce. When those denunciations come hedged with qualifiers that rest on propaganda lines, they ring entirely hollow.

Germans get this. Angela Merkel’s party, the conservative Christian Democratic Union, always understood that if you’re going to stand even half an inch to the right of center in the country that Hitler once ran, you must go to very great lengths to put distance between yourself and anything even vaguely reminiscent of Nazism. Which is one reason the center-right in Germany is one of the most doggedly pro-democracy forces in Europe.

Sanders needs to understand he’s in a similar position. He has chosen to describe himself using the same word that totalitarian leaders have chosen to describe themselves. He must take on a special responsibility to make it entirely unambiguous that he’s wise to the propaganda games authoritarian socialists use to bolster their power. Holding him to that standard is in no way unreasonable.

When Sanders parrots Fidel’s propaganda, he fails the test. And many Latinos and people in Latin America notice. We have a hyper-developed nose for propaganda. It sends us reeling. Because we know this game from the inside.

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