Donald Trump’s 2024 campaign rhetoric echoes the racist screeds written by white supremacist mass shooters; the chants of the tiki torch-wielding neo-Nazis who marched in Charlottesville, Virginia; and the disgusting, profoundly false theses penned by eugenicists and so-called race scientists.

Although he launched his successful 2016 bid for the White House by labeling Mexican immigrants “rapists” and calling for a ban on Muslims entering the U.S., the severity of the GOP presidential nominee’s rhetoric this election season marks an escalation — one that has seen some political observers, once hesitant to call Trump a “fascist,” suddenly more at ease with the label.

“People were very careful early on not to compare him to Hitler, and to not use the term ‘fascist,’ because people thought it was an exaggeration,” Ernesto Castañeda, a professor at American University who directs The Immigration Lab and the Center for Latin American and Latino Studies, told HuffPost.

“When he was in power, it was not a fascist regime, but his campaign rhetoric right now — the rally [that] took place in Aurora, Colorado, I listened to the whole thing, and it could have been a Nazi speech from a reel in English. The people shouting, the people saying hateful things and the crowd going crazy. He had clips of incidents with immigrants committing crimes, running one after the other, from different media sources, credible and otherwise. It was really, really emotional. Really, really trying to move somebody that wasn’t informed.”

A dispatch from The New York Times described Trump’s anti-immigrant campaign speech in the Denver suburb of 400,000 on Oct. 11 :

Mr. Trump repeated claims, which have been debunked by local officials, that Aurora had been “invaded and conquered,” described the United States as an “occupied state,” called for the death penalty “for any migrant that kills an American citizen” and revived a promise to use the Alien Enemies Act of 1798 to deport suspected members of drug cartels and criminal gangs without due process.

Such rhetoric has become boilerplate in Trump speeches, interviews and social media posts. In recent months the former president has called for immigrants in the U.S. to undergo “remigration,” a well-known euphemism for mass deportations with links to European fascist movements. His use of the term corresponds with his campaign promise to expel millions of immigrants from the country once in office.

Trump, with support from his next-gen authoritarian running mate, Sen. JD Vance, has also pushed the lie that Haitian migrants in Springfield, Ohio, are eating their neighbors’ pets — a baseless, thoroughly debunked accusation, previously promoted in the state by a neo-Nazi group, that recalls historical fascist narratives depicting marginalized groups as savages. (Such anti-Haitian racism was especially pronounced among American white supremacists in the 1990s, with former Ku Klux Klan leader David Duke insisting Haitians should not be allowed in the country because they were not of “European descent.”)

Trump has also said that many immigrants — a group largely composed of Black and brown people — are “murderers,” claiming that they are immutably, biologically criminal.

“Many of them murdered far more than one person, and they’re now happily living in the United States,” he said during an appearance on “The Hugh Hewitt Show” earlier this month. “You know, now a murderer, I believe this, it’s in their genes. And we got a lot of bad genes in our country right now. They left, they had 425,000 people come into our country that shouldn’t be here, that are criminals.”

Aside from the statistics Trump was misleadingly citing to criticize Democrat Joe Biden’s presidency, his argument that these immigrants have “bad genes” echoes some of the most vile eugenics and race science pushed throughout American history to give systemic racism an academic sheen — and to justify horrifying policies like mass sterilization.

And when it comes to next month’s presidential election, Trump has said Jewish voters will be to blame if he loses, as will noncitizens fraudulently casting ballots.

The latter accusation is at the heart of Trump’s apparent plan to deny the results of the election if his Democratic rival, Kamala Harris, is declared the winner. For months, he and the GOP have been laying the groundwork to blame a loss on immigrants — a claim reminiscent of the white supremacist “great replacement” conspiracy theory, which maintains that Black and brown immigrants, often at the behest of Jews, are flooding into America and Europe to “replace” white people. The theory has helped inspire multiple mass shootings in recent memory — including in Pittsburgh, Pennsylvania; El Paso, Texas; and Buffalo, New York — and was the basis for the infamous chant at 2017’s deadly neo-Nazi rally in Charlottesville: “You will not replace us!”

According to journalist Bob Woodward’s book “War,” retired Army Gen. Mark Milley, who served as chair of the Joint Chiefs of Staff under Trump and Biden, has called Trump a “total fascist.”

“He is the most dangerous person ever,” Milley told Woodward. “I had suspicions when I talked to you about his mental decline and so forth, but now I realize he’s a total fascist. He is the most dangerous person to this country. ... A fascist to the core!”

Now, with less than three weeks to go until the election, Trump is signaling that he’ll escalate his rhetoric further, according to a report in Rolling Stone.

The outlet wrote:

In recent conversations with close allies, the former and perhaps future president has stressed that he can’t — as some advisers apparently would like him to — play it safe in these final weeks of campaigning, two people familiar with the matter tell Rolling Stone. “That’s how you lose,” Trump told one small huddle of these allies, one of the sources relays, as he emphasized that, especially on immigration, he needs to slam his foot on the gas.

Academics like Castañeda, who have studied genocides to examine how speech can lead to violence, are ringing the alarm bells about Trump. “You just need a few individuals to take him at his word and actually act on it for people to be hurt,” he told HuffPost.

Castañeda pointed to the El Paso shooting in 2019, when a white supremacist opened fire at a Walmart, killing over 20 people in a massacre that amounted to one of the deadliest anti-Hispanic hate crimes in U.S. history. Although it’s difficult to draw a direct line between Trump’s rhetoric and the massacre, the shooting occurred during a time of intensifying right-wing rhetoric, spearheaded by Trump and Fox News, depicting immigrants at the border as “invaders.”

“So that ideology in the speeches of Donald Trump and the actions of people that actually have done mass shootings, they are all connected,” Castañeda said. “They are all in the same circle. They are talking to each other. And they have more or less the same goal of having or assessing power and keeping some group in power, and making sure that the other groups are deported, secluded, put in concentration camps — which Trump has openly said he will do — or that at least they don’t have any more ascendancy, influence or political power in the U.S.”

Susan Benesch, a director of the Dangerous Speech Project nonprofit and a faculty associate at Harvard University’s Berkman Klein Center for Internet & Society, said it’s often a mischaracterization to call rhetoric like Trump’s “hate speech.”

“If you are trying to understand what makes people dangerously angry at another group of people, it’s not hatred; it’s fear,” Benesch said. “Hatred is, in fact, hard to define. Fear is not hard to define at all, and fear, very importantly, is connected to biological responses in the human body. When people are afraid, they have physiological responses to that.”

“So, for example, telling your supporters that other people are eating pets is absolutely brilliant, because one of the generalizations you can make about human beings is … that they care enormously about pets,” she said.

But what political advantage does Trump gain by using such rhetoric?

“He presents himself as the only savior, the only solution,” Benesch said. “He says all these people, and lists them at different times — Muslims, Haitians, Mexicans, Democrats, Democratic leadership, the deep state — all of these awful people are trying to hurt you badly. And the only solution is me. He says this all the time — ‘Only I can protect you.’ … So the formula is: Here’s this terrible, terrible, horrible threat, be extremely afraid, and now the only way out, the only solution to this horrifying threat is me. So then, of course, you’ve got to vote for him.”

And then some of his supporters will likely go further than voting. Trump’s invitation to his followers to a Jan. 6, 2021, rally in Washington, D.C., included his now-infamous words, “Be there, will be wild!” But there had been months of “threat construction” before that, Benesch said. Trump depicted the 2020 presidential election as stolen by the so-called deep state and a host of other perceived enemies who posed an existential threat to the “Make America Great Again” faithful, driving his supporters to call for the hanging of then-Vice President Mike Pence and to hunt the halls of Congress looking for prominent Democrats.

Part of what makes Trump so dangerous, Benesch said, is the sprawling right-wing media ecosystem that works overtime to fine-tune his fascist talking points — and to spread them far and wide. She often points to how during the tribunal after the Rwandan genocide, two prominent radio executives and a newspaper editor were taken to court for their responsibility in fomenting the mass killing.

“[A] witness was asked, ‘What did these men do to bring about the genocide?’ since they hadn’t, as far as anybody knew, touched a machete. And the witness said, ‘They dribbled petrol little by little all over the country, so that one day you could strike a match and it would burst into flame,’” Benesch said.

“This is a very important point that is often missed in discussions about inflammatory rhetoric that nobody is exposed to it just once — they get exposed to it over and over and over and over and over, and eventually a human mind can be soaked in petrol, and then that person is ready to burst into a violent response.”

A recent poll by the Public Religion Research Institute found that a large swath of the American public is susceptible to authoritarianism, with many open to the idea of political violence.

“Our new survey finds that four in ten Americans are susceptible to authoritarian appeals, and that number rises to two-thirds of Republicans and white evangelical Protestants,” Robert P. Jones, PRRI’s president and founder, said in a press release. “Notably, while the vast majority of Americans reject the use of political violence, those who support authoritarianism are nearly twice as likely as the general public to support it.”

Jones added, “These findings should serve as an important warning as we enter an election season that is incredibly consequential for the health of American democracy.”