The garbage has a familiar smell

The 180-page manifesto the alleged teenage mass shooter posted online prior to attacking a grocery store in a predominantly Black neighborhood in Buffalo, N.Y., is chilling.

Not because his ideas about a "great replacement" of white people are deranged — and they certainly are.

But how familiar they sound.

The 18-year-old suspect quotes liberally from similar manifestos, including the one posted before Brenton Tarrant gunned down 51 people at two New Zealand mosques. If you're a history buff, you can easily trace the sentiment backward to at least the early 1900s, when the targeted ethnic groups also included Catholics, Jews and eastern European immigrants.

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More recently, you've likely heard similar vitriol spouted by your racist uncle, right-wing TV personalities like Tucker Carlson and, yes, even sitting members of Congress.

“For many Americans, what seems to be happening or what they believe right now is happening is, what appears to them is we’re replacing national-born Americans, native-born Americans to permanently transform the landscape of this very nation," U.S. Rep Scott Perry said, at a House committee meeting last year.

Perry couched that racist trope using the old "people say" trick to avoid personal accountability. But his intent was clear.

The racist dog whistle has become a bull horn and many elected officials — let's be clear: Republicans — feel completely at ease repeating it.

Payton S. Gendron, the killer of 10 people in Buffalo who'd just been going about their day is one of those "many Americans" Perry invoked in Congress, according to reporting by The New York Times and others.

And he parrots so many of the familiar racist talking points we've seen come out of the mouths of right-wing talking heads.

From Gendron's manifesto: “Why is diversity said to be our greatest strength?"

From Carlson's Fox News show: "How, precisely, is diversity our strength?”

Carlson and Perry stopped short of prescribing a solution as they spread this vile conspiracy theory about the "replacement" of native-born Americans. But their messages led some to an obvious and chilling conclusion.

In his manifesto, Gendron described the aim of his attack as a warning to nonwhite people: "Leave [white territory] while you still can, as long as the White man lives you will never be safe here.”

As best we can tell, Perry has steadfastly avoided being held to account for his recitation of racist propaganda. Carlson, meanwhile, has batted away criticism by invoking concern for "voting rights."

But their words have consequences.

According to a recent Associated Press poll, one-third of Americans reported that they're concerned that “native-born Americans are losing economic, political, and cultural influence in this country because of the growing population of immigrants."

How many more Payton Gendrons are out there, looking for ways to put this white supremacist rhetoric into practice?