The Manson murders — the seven killings committed by Charles Manson’s followers in two days in Los Angeles in August 1969 — are often thought to mark the end of the 1960s, as if those brutal slayings were the inevitable outgrowth of the counterculture, the dark consequence of long hair, free love, casual drug use and a general breakdown of authority and social norms.

This sentiment was most famously expressed by Joan Didion in her book “The White Album.” She wrote that “in a sense” it was true that “the Sixties ended abruptly on August 9, 1969, ended at the exact moment when word of the murders on Cielo Drive traveled like brush fire through the community.”

But with some historical distance, and after Mr. Manson’s death on Sunday at age 83, we can see that the simplistic counterculture dichotomy of “freaks” versus “squares” caused people to lump Mr. Manson in with the freaks (for he certainly wasn’t a square). Apart from the long hair and the casual sex, however, Mr. Manson, who spent much of his life in prison with a swastika carved into his head, had more in common ideologically with far-right groups like the John Birch Society than he did with the anarchic leftism of, say, the Yippies.

Mr. Manson was not the end point of the counterculture. If anything, he was a backlash against the civil rights movement and a harbinger of white supremacist race warriors like Dylann Roof, the lunatic fringe of the alt-right.

Mr. Manson was famously inspired by the Beatles song “Helter Skelter,” which, as he understood it, described a race war that he had been prophesying. Like many reactionaries, he saw race in America in apocalyptic terms. He believed that African-Americans would soon rise up and begin to murder white people. Mr. Manson and his followers would be spared; they were going to hide beneath the desert in Death Valley until the war was over, when they would surface from their underground lair and rule over the black population, which, Mr. Manson claimed, would be unable to govern itself.

But when this race war proved too slow in coming, Mr. Manson urged his followers to set it in motion themselves, to “do what blackie didn’t have the energy or the smarts to do — ignite Helter Skelter and bring in Charlie’s kingdom,” as Tex Watson, a member of Mr. Manson’s “family,” recalled. Mr. Manson assumed that the murders of wealthy, white Angelenos would be blamed on African-Americans and the race war would begin.

Joan Didion described them as “senseless killings.” But they were not senseless. They were racist.

Today, this sort of logic is all too familiar to us. The paranoid, racist and apocalyptic ramblings of Mr. Manson are the DNA of the reactionary alt-right. In the days leading up to Dylann Roof’s murder of nine black parishioners at Emanuel African Methodist Episcopal Church in Charleston, S.C., he talked to his friends about a “race war” and later used the same language in interviews with investigators. He was an enthusiastic reader of alt-right websites.

In recent months, the far-right media have become fixated on the idea that left-wing “antifa” activists will spark a new civil war. Gateway Pundit, a far-right website, claimed that “millions of antifa supersoldiers will behead white parents,” and Alex Jones, the conspiracy enthusiast who runs the website Infowars, predicted that the antifa activists would lose such a war.

White supremacists like Richard Spencer have realized, of course, that by wearing slick suits and sporting stylish haircuts they can be both edgy and respectable at once. They are fighting a culture war (and have even embraced the term “counterculture” in recent years). In that spirit, a recent essay by Vincent Law on AltRight.com, Mr. Spencer’s website, granted that though “I love fantasizing about RAHOWA” — racial holy war — a culture war among “good” and “bad” whites will have to come first.

This sort of rhetoric, like Mr. Manson’s, is predicated on manipulating the Tex Watsons and Dylann Roofs of the world, of making them do the dirty work to bring about the world in which their masters will rule. That is not the inevitable outgrowth of the 1960s counterculture. That is the apocalyptic racism of too many eras, including our own.

Baynard Woods