Donald Trump won’t be president for life. In a little more than two or (heaven help us) six years, he will be gone. But his baleful legacy will live on. He is turning U.S. politics into a Superfund site and the Republican Party into the leading intellectual polluter in America. It could take a generation to clean up the toxins he has released. Trump is a racist, xenophobe and conspiracy-monger, and his party increasingly reflects all of those mental deformities.

Trump suggests that Florida’s efforts to count ballots after Election Day — a standard practice — are part of a Democratic plot to steal the election. “An honest vote count is no longer possible-ballots massively infected,” he tweeted. “Must go with Election Night!” There is no evidence — none — of any fraud. When asked for proof, Trump replied, “I don’t know. You tell me.”

But his conspiracy-mongering is echoed by governor and Senate candidate Rick Scott (R), who vows “I will not sit idly by while unethical liberals try to steal this election,” and by Sen. Marco Rubio (R-Fla.), who claims, “Incompetent law breaking election officials lead to chance for lawyers to steal an election.” I worked on Rubio’s 2016 presidential campaign, so I am saddened to see “Little Marco” turning into his tormentor’s mini-me.

But that is the Trump effect: He is pushing otherwise sane Republicans down conspiratorial rabbit holes. It is big news when Republican Martha McSally in Arizona is willing to graciously concede her Senate race without claiming she was the victim of fraud. What used to be routine is now extraordinary.

McSally is, after all, a member of the same party as Rep. Matt Gaetz (R-Fla.). He tweeted a video of a man handing currency to women and girls under the caption: “BREAKING: Footage in Honduras giving cash 2 women & children 2 join the caravan & storm the US border @ election time. Soros? US-backed NGOs? Time to investigate the source!” Trump retweeted the video, writing: “Can you believe this, and what Democrats are allowing to be done to our Country?” It turned out the footage was from Guatemala, not Honduras, and it showed local merchants contributing money to the refugee caravan. There was no connection to George Soros, but that hasn’t stopped Trump, Gaetz & Co. from trafficking in this anti-Semitic conspiracy theory.

Trump also hasn’t been shy about insulting the intelligence of African Americans. Rep. Maxine Waters (D-Calif.), one of the longest-serving members of the House, is an “extraordinarily low I.Q. person.” CNN anchor Don Lemon is “the dumbest man on television” and makes LeBron James “look smart, which isn’t easy to do.” CNN reporter Abby Phillip, a Harvard University graduate, asks “a lot of stupid questions.” Stacey Abrams, a Yale Law School graduate and former minority leader of the Georgia House of Representatives, is “not qualified” to be governor of Georgia. Trump insults lots of people, including whites such as CNN’s Jim Acosta (“a rude, terrible person”), but his barbs about intelligence are primarily aimed at minorities.

Latin American immigrants are another favorite Trump target. In the midterm campaign, he released a commercial trying to make a cop-killer the symbol of a supposed invading army of illegal immigrants. The ad was so racist and dishonest that not even Fox News , his favorite network, would air it.

Such blatant bigotry from the president encourages blatant bigotry among his followers. Rep. Steve King (R-Iowa) refers to Mexican immigrants as “dirt,” Florida gubernatorial candidate Ron DeSantis warns voters not to “monkey this up” by electing his African American opponent, and Sen. Cindy Hyde-Smith (R-Miss.), who represents a state with a long history of lynching, jokes about being in the front row for a “public hanging.”

Trent Lott, a former senator from Mississippi, had to resign as Senate majority leader after “joking” that if only the Dixiecrat Strom Thurmond had been elected president in 1948, “we wouldn’t have had all these problems.” But that was in 2002, when the GOP still had some standards. Today, Trump has given the haters permission to come into the open. Little wonder that the FBI reports that hate crimes were up 17 percent last year and anti-Semitic hate crimes up 37 percent. After Trump pronounced himself a “nationalist,” the founder of the neo-Nazi Daily Stormer website gleefully exclaimed: “He is /ourguy/. He is pushing the edges of the limits.”

Trump is not just pushing the limits — he is erasing them. He is normalizing bigotry and conspiracy-mongering in ways that would have seemed unimaginable only a few years ago. After he is gone, and perhaps even before, it will be imperative to rebuild the guardrails of our culture. We cannot eliminate bigotry, but we can reduce its prevalence and make its public expression unacceptable. The anti-tobacco campaign publicizing the dangers of smoking offers a model of the kind of public-education effort that will be necessary to clean up Trump’s toxic residue. Because if history teaches anything, it is that hate-mongering kills just as surely as smoking does.

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