Jonathan Zimmerman

Opinion contributor

Let’s suppose that a teacher stood up in front of her class and said students should go back to the corrupt countries from which they came. What would happen?

We all know the answer. She would be fired, and justly so. The comment is racist to its core, and it has no place in a school classroom.

That’s why all of our schools — and all of our teachers — should denounce President Donald Trump’s recent comments about four Democratic congresswomen. Schools are required to teach the skills and habits of democratic life: civility, tolerance and mutual respect. When the president breaches those norms, we have to call him out.

At the same time, however, we also need to guard against vilifying students who support Trump. Our message must be clear and unequivocal: They can like the president. They just can’t act like him, insofar as he violates the principles that undergird democracy itself.

Support Trump policy, not behavior

That’s what Trump did, in a series of comments about Reps. Ilhan Omar of Minnesota, Rashida Tlaib of Michigan, Ayanna Pressley of Massachusetts and Alexandria Ocasio-Cortez of New York. On Sunday,he tweeted that the four lawmakers should “go back and help fix the totally broken and crime infested places from which they came.” He doubled down on the slur the following day, using his all-caps button to tweet, “IF YOU ARE NOT HAPPY HERE, YOU CAN LEAVE.” Then he tripled down Wednesday at his North Carolina rally, which erupted in chants of "send her back" when he attacked Omar.

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Never mind that Omar is the only one of the four who actually came to America from another country, or that white supremacists welcomed Trump’s remarks. “It doesn’t concern me, because many people agree with me,” the president said, when asked about racist support for him.

This is precisely why our schools need to teach a different lesson. Reasonable and decent people can disagree about Trump’s policies on immigration, taxes and everything else. Yet no reasonable or decent person would tell another American to leave the country simply because of that person's opinions or racial background.

That’s why the school board in Fort Worth, Texas, recently fired a teacher who posted on social media that her district was “loaded with illegal students” and that Trump should help remove them. When a student asked to go to the bathroom, she also allegedly said, “Show me your papers that are saying you are legal.”

And it’s also why a substitute teacher in Los Angeles was dismissed for telling her students — on the day after Trump was elected — that their parents would be deported. “If you were born here, then your parents gotta go and they gonna leave you behind,” she reportedly said. “You’ll be in foster care."

These teachers are free to believe whatever they want about Trump, immigration and everything else. But they should not be allowed to slur immigrants — or anybody else — in the racist manner that Trump does.

Not all Trump fans are racist

Simultaneously, though, we also must take pains not to slur all Trump supporters as racist. Surely some of them are, as white-supremacist praise of Trump's tweets confirmed. But denouncing every Trump voter as a bigot echoes the same intolerance that Trump himself has injected into our public discourse.

Witness the Virginia teacher’s assistant who allegedly called a student wearing a Trump 2020 flag “racist and sexist.” She also reportedly tried to shove the flag — which bore Trump’s signature slogan, “Make America Great Again” — down the student’s shirt.

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Or consider the Georgia teacher who was placed on leave — and later resigned — after she asked two students to turn their MAGA T-shirts inside out. She also told her students that wearing Trump’s slogan was like displaying a Nazi swastika.

Leave aside the fact that28% of Hispanics casting ballots in 2016 voted for Trump, who polled better than Mitt Romney did with that group in 2012.Teachers have no business denouncing an entire category of voters, any more than they should slur people on the basis of their race or immigrant status.

Good citizens show respect, decency

But nor should our teachers shirk from identifying blatantly racist statements when the president of the United States makes them. So far, most GOP politicians have kept quiet in the face of Trump’s bigoted barrage. Our teachers can’t — and shouldn’t — do that. Their job is to prepare future citizens for democracy, which requires us to treat each other with dignity and respect.

Trump’s recent comments about the four congresswomen fly in the face of that. So do his claims that Mexicans are rapists, and that African countries are s---holes. No decent human being talks that way. No decent parent would let their children talk that way.

And if they do, our schools need to teach a better way. There are no two sides here, and every reasonable person knows that. No matter what we believe about President Trump, we must make sure our children do not behave like him. The entire fate of our democracy rests on that distinction. Shame on us if we lose sight of it.

Jonathan Zimmerman teaches education and history at the University of Pennsylvania. He is co-author of “The Case for Contention: Teaching Controversial Issues in American Schools.”