When President Trump tweeted Wednesday night that he had asked Secretary of State Mike Pompeo to look into violence against, and seizures of land from, white farmers in South Africa, he wasn’t just amplifying a narrative he heard from Fox News host Tucker Carlson.

Trump was also elevating a storyline that has floated around white supremacist blogs, podcasts and online forums for years. And the president’s tweet shows how these white supremacist ideas bubble up from the Internet’s darkest corners into the Oval Office.

In 2015, Dylann Roof walked into a Bible study group at Emanuel African Methodist Episcopal Church in Charleston, S.C., listened quietly for an hour and then opened fire, killing nine people. A photo that later surfaced online showed Roof wearing a jacket sporting the flag of South Africa’s apartheid regime. The 24-year-old South Carolinian clearly felt an affinity with white South Africans.

That sentiment is common across the white supremacist universe.

The neo-Nazi website the Daily Stormer has published hundreds of stories about the plight of white South African farmers. Users of the white supremacist site Stormfront have been going on about the issue for years. White nationalist groups on platforms such as Facebook are similarly devoted the fate of South African whites.

These narratives often portray the treatment of South African whites as a critical front in an imagined global fight against white people. If whites in South Africa are treated so poorly after handing over power to the country’s black majority, the story goes, it’s just a preview of what could happen in the rest of the world as more diverse voices are allowed into the political conversation. This fear has been given a name: white genocide.

In the leaked logs of an online white nationalist chat server operated by South African Willem Petzer, published by the independent media outlet Unicorn Riot, users explicitly discussed highlighting this story as part of a larger propaganda goal. “Are we selling this white genocide lie in SA as well as the jews did with the holocaust in ww2?” one user wrote, equating the neo-Nazi conspiracy theory that the Holocaust never happened with a desire to use inflated claims about the treatment of South African farmers to further the cause of white nationalism. “We need to build some head lice treatment rooms/showers,” replied another, blithely nodding at killing methods methods used in Nazi concentration camps. “I think that may solve the problem.”

The white nationalist version of what’s happening in South Africa is a twisted history of the land reforms that have been instituted since apartheid ended in 1994. The claim is that black South Africans are increasingly invading white farms, slaughtering farmers and claiming their land for themselves.

But there’s no evidence of a genocide against white South Africans.

“There’s no truth to this story whatsoever,” said Ben Cousins, a senior professor at the Institute for Poverty, Land and Agrarian Studies at the University of the Western Cape in South Africa. “Every now and then, a white person is robbed or killed on a farm, but the murder rate is far higher for black South Africans. This is just an attempt by the far-right to whip up a frenzy.”

While there are certainly cases of white farmers being attacked and murdered in South Africa, the number of those attacks had decreased steadily since a peak in 2001, until last year, when they rose slightly. In 2001, there were 1,069 farm attacks and 140 murders in South Africa. By 2017, that had dropped to 561 attacks and 47 murders, according to the South African Police Service. About 61 percent of murder victims in farm attacks even during the peak were white, according to a 2003 study.

Trump likely isn’t personally crawling through obscure Internet forums to learn about agrarian South African politics. Instead, his information is being filtered through Fox News, which has increasingly played a role in spreading ethno-nationalist rhetoric.

“Tucker Carlson has become our hate mainstreamer in chief,” said Heidi Beirich, who leads the Southern Poverty Law Center’s Intelligence Project on hate and extremism.“ He seems to be picking up the thinking of the white supremacist movement in the United States and expressing it in very harsh terms.... This isn’t a dog whistle. This is just a blatant repeating of white supremacist ideas.”

Carlson’s repeated surfacing of white supremacist rhetoric has earned him a devoted set of fans among online racists. On the far-right social network Gab, there are user-created groups devoted to fawning conversations about Carlson’s show. Other groups on the platform promote neo-Nazi ideology or act as whites-only job search boards.

Trump has pushed the narrative of white genocide into the national conversation before. During the 2016 presidential campaign, he retweeted a Twitter user with the handle @WhiteGenocideTM.

But Wednesday night marked the first time he has referenced white South Africans directly. And white supremacists celebrated.

“IT’S HAPPENING: Trump Tweets About WHITE GENOCIDE in South Africa” blared a headline on the Daily Stormer. “This is a fairly significant step in the right direction,” read an article on the white supremacist site Infostormer. “Trump’s involvement is going to draw even more attention to the plight of White farmers in South Africa.”

On Stormfront, Trump’s tweet was seen a welcome sign of an impending race war that users hope will drench the planet in a cleansing bloodbath. “It’s a start,” one Stormfront user wrote. “Regardless where I’ll be in the world, when the shooting starts I’ll be on my way back.”

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