On Sunday night, President Donald Trump tweeted out an excerpt from a CNS News column written by Pat Buchanan, a former senior adviser to Presidents Richard Nixon, Gerald Ford, and Ronald Reagan, that makes a white nationalist case for Trump’s border wall.

Trump’s decision to promote Buchanan’s article hints at how his push for a border wall is rooted in more than concerns about national security and keeping drugs out of the country — it’s also about keeping America as white as possible.

Trump first tweeted a portion of Buchanan’s piece that mentions crimes committed by undocumented immigrants — a favorite topic of Trump’s when he’s been making his sales pitch for the wall lately. (Undocumented immigrants are in fact less likely to commit crimes than native-born Americans.)

The Trump portrait of an unsustainable Border Crisis is dead on. “In the last two years, ICE officers made 266,000 arrests of aliens with Criminal Records, including those charged or convicted of 100,000 assaults, 30,000 sex crimes & 4000 violent killings.” America’s Southern.... — Donald J. Trump (@realDonaldTrump) January 14, 2019

Trump then tweeted another excerpt, followed by his own commentary that “The great people of our Country demand proper Border Security Now!” — a claim contradicted by polling showing Americans don’t support a border wall in general, nor do they support Trump’s move to force a government shutdown in hopes of securing funding for it.

....Border is eventually going to be militarized and defended or the United States, as we have known it, is going to cease to exist...And Americans will not go gentle into that good night. Patrick Buchanan. The great people of our Country demand proper Border Security NOW! — Donald J. Trump (@realDonaldTrump) January 14, 2019

What Trump did not share, however, is the closing section of Buchanan’s column — one that makes an explicitly white nationalist case for a border wall.

After accusing Democrats of having “a demographic and ideological interest in changing the face of the nation,” Buchanan writes that “For the larger the share of the US population that requires welfare, the greater the need for more social workers, and the more voters there will be to vote to further grow the liberal welfare state.”

He continues:

The more multiracial, multiethnic, multicultural, multilingual America becomes — the less it looks like Ronald Reagan’s America — the more dependably Democratic it will become. The Democratic Party is hostile to white men, because the smaller the share of the U.S. population that white men become, the sooner that Democrats inherit the national estate. The only way to greater “diversity,” the golden calf of the Democratic Party, is to increase the number of women, African-Americans, Asians and Hispanics, and thereby reduce the number of white men.

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Trump has backed ideas along the lines of Buchanan’s in the past. Last year, he endorsed a Republican immigration bill that would have restricted legal immigration and given English speakers preferred status. Buchanan supports making English the official language of the US.

Trump’s public embrace of Buchanan is ironic, considering that during an interview 20 years ago, Trump cited Buchanan’s views and concluded, “It’s just incredible that anybody could embrace this guy.”

“Look, he’s a Hitler lover,” Trump said on Meet the Press in 1999. “I guess he’s an anti-Semite. He doesn’t like the blacks. He doesn’t like the gays. It’s just incredible that anybody could embrace this guy.”