Donald Trump is priming the pump when it comes to his "dehumanizing" language, an authoritarianism expert said on Saturday.

New York University professor Ruth Ben-Ghiat appeared on CNN Newsroom with Jim Acosta, where she was asked about comments the former president made earlier in the day. Specifically, Trump once again said that migrants are "poisoning the blood of our country," repeating language purportedly used by Hitler and other dictators.

"You've studied fascist rhetoric, you and I have discussed this many times. What was your reaction when you heard Trump say this earlier today?" Acosta asked of his guest, Ben-Ghiat.

She replied, "This is fascist rhetoric. The worries about polluting the blood of the superior race go as a standard of Nazism. It's not just the Nazis. It's also fascists, Italy. Mussolini literally talked about killing rats, to go back to Trump's use of vermin in an earlier speech. He talked about killing rats, who were bringing infectious diseases and communism into Italy."

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She added that, "This is fascist rhetoric and he's using it for a very precise purpose."

The important question for Ben-Ghiat is "why he's using it now so often?"

She explained:

"And unfortunately, the Trump campaign has made it very clear what they want to do to immigrants. Mass deportations, mass detentions, likely abuses and violence in those operations. And, you know, dehumanizing immigrants, which is what this language does, is a way to get Americans prepared now to accept these repressions later on. That's what's so terrible, and that's also another thing that's so fascist about this."

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