Previously published at WGBHNews.org.

It was an irresistible hook at a moment of horror: Squirrel Hill, the heavily Jewish neighborhood in Pittsburgh where a hate-mongering gunman killed 11 people at the Tree of Life Synagogue on Saturday, was the home of the late Fred Rogers, the otherworldly host of “Mister Rogers’ Neighborhood.”

“It doesn’t just feel like a ‘Mr. Rogers kind of neighborhood’ — it was Mr. Rogers’ neighborhood,” wrote my friend and former Northeastern colleague Dina Kraft in the Israeli newspaper Haaretz. New York Times columnist Bari Weiss, whose bat mitvah was held at Tree of Life after her family’s regular synagogue burned down, recalled Jews and gentiles working together to put out the fire:

As Beth Shalom’s executive director told a reporter at the time: “I didn’t have to look — everyone came to me.” The line put me in mind of my favorite of Fred Rogers’ sayings. “When I was a boy and I would see scary things in the news, my mother would say to me, ‘Look for the helpers. You will always find people who are helping.'”

Last summer we saw the Fred Rogers documentary “Won’t You Be My Neighbor?” Rogers was not a major part of my life. I was too old for his original television show, and by the time we had kids the program was fading away. But I’ve thought about Rogers quite a lot since seeing the film and have wondered what this profoundly unhateful, uncynical children’s advocate would say about what is happening to us.

How might things be different if the Pittsburgh shooter had been exposed at the right time in his life to someone as devoted to the emotional development of children as Rogers? Or the conspiracy-minded Florida man who was arrested last week and charged with sending pipe bombs to high-profile liberal and media targets such as the Clintons, U.S. Rep. Maxine Waters, and CNN? Or the racist white Kentucky man who authorities say walked into a supermarket last week and murdered two elderly African-Americans — but only after he tried and failed to enter a black church?

Or — it has to be said — what if someone like Fred Rogers had been able to reach President Trump at a young age?

I find myself feeling more sad than angry. That sadness stems not just from the terrible events that have taken place during the past week but from the certainty that our president has helped stoke the right-wing lunacy that has been unleashed upon us. Trump does not care about the consequences of his words as long as he believes they will advance his own selfish interests.

There has been much speculation in recent days — renewed speculation, that is — as to whether Trump is an anti-Semite, notwithstanding the fact that some members of his own family are Jews. I think that’s the wrong question. So what if, in his heart, he does not harbor anti-Semitic views? What matters is that he is willing to use anti-Semitism when it suits him, just as he is willing to use racism, homophobia, transphobia, Islamophobia, and misogyny. Meanwhile, anti-Semitism is on the rise, according to the Anti-Defamation League.

Rich Lowry, a callow opportunist who passes for a responsible conservative by the low standards of our times, had the temerity to sneeringly ask on Twitter: “What’s even the theory supposed to be that Trump is an anti-Semite?” That brought about a devastating retort from the journalist Mehdi Hasan, who pointed out that Trump has engaged in such dubious behavior as consorting with white nationalists and attacking “globalists,” a euphemism for educated Jews.

Much of the Trump-inspired hysteria of the past few weeks can be tied to the president’s exploitation of the so-called caravan of Honduran immigrants who have left their country to escape violence. Never mind that they are in southern Mexico and that few of them have much chance of entering the United States. Trump and his sycophants on Fox News and elsewhere have conflated this into some sort of George Soros-financed (that is to say, Jewish) plot to flood the country with illegal aliens — I am using their term, not mine — so that they can vote for Democrats on Nov. 6. The alleged Pittsburgh shooter specifically cited this bizarre theory in a post on Gab, which has been described as a social platform for anti-Semites. Adam Serwer of The Atlantic explains:

The apparent spark for the worst anti-Semitic massacre in American history was a racist hoax inflamed by a U.S. president seeking to help his party win a midterm election. There is no political gesture, no public statement, and no alteration in rhetoric or behavior that will change this fact. The shooter might have found a different reason to act on a different day. But he chose to act on Saturday, and he apparently chose to act in response to a political fiction that the president himself chose to spread and that his followers chose to amplify.

Trump himself has doubled down on his rhetoric, tweeting that “Gang Members and some very bad people” are part of the caravan and repeating his dangerous assertion that the media (oops, sorry, just the “fake news” media) are “the Enemy of the People.”

No doubt Trump is scared. If the Republicans lose one branch of Congress in November, he will finally face the prospect of a serious investigation on Capitol Hill — an investigation that is almost certain to document all manner of wrongdoing. He is willing to say anything to prevent that from happening. As ugly as his rhetoric has been, it is likely to get worse — and damn the consequences. Josh Marshall, for instance, wrote the other day about a new Trump ad that reeks of anti-Semitism.

We have come a long way from Mr. Rogers’ neighborhood. And we are all the worse for it.

Talk about this post on Facebook.