Before border-patrol agents separated migrant families, before the White House declared a ban on Muslims, before the U.S. Army deployed troops to the border, before the Trump administration’s raids, restrictions, and deportations, Steven Miller e-mailed Breitbart.

He was excited. It was March 2015. Miller, then an aide to the notoriously anti-immigration Alabama senator Jeff Sessions, had discovered the perfect occasion to condemn immigration. “They opened the Ted Kennedy center today in Boston,” Miller wrote to editor Katie McHugh. “Another opportunity to revisit the ’65 immigration law.” At the instigation of Miller, Breitbart published an article disparaging Kennedy’s “ruinous” immigration policy. The law in question was the Immigration and Nationality Act of 1965, otherwise known as the Hart-Celler Act. And the bill ended race-based limits on immigration, like the Immigration Act of 1924, which enacted severe national quotas and was based on the junk-science eugenics movement. Yet, according to Breitbart, the 1965 bill didn’t represent a new era of American public policy freer of discrimination but a new generation of foreigner-driven rape, murder, and unemployment across the United States.

McHugh wrote that “the costs Americans pay in lowered wages, strained social safety nets, their children’s blood, their declining quality of life, the chaos of sharing space with an ever-swelling criminal population aided and abetted by the nation’s elite, the berating Americans of every stripe endure when they dare ask their country merely be preserved—that’s the real legacy of Ted Kennedy.”

The e-mail exchange between McHugh and Miller was among a trove of over 900 messages analyzed in an exposé published this week by the Southern Poverty Law Center (SPLC). Among Miller's notes and calls are links to white nationalist websites, like VDARE and American Renaissance, and a recommendation for a French dystopian novel, The Camp of the Saints, popular among neo-Nazis, which depicts a rampaging mass of brown refugees literally eating feces and raping white women. Miller also repeatedly praised the immigration law endorsed by Adolph Hitler—in Mein Kampf, the Nazi leader praises the U.S. race-based Immigration Act of 1924, signed into law by President Calvin Coolidge. The leaks caused a stir. The news that Miller was trading in extremist white supremacist propaganda was—and should be—deeply disturbing. Ethnonationalism with a foothold in the White House is disheartening, but it's also not exactly new.

Far from the radical heyday of Abraham Lincoln, the modern Republican Party has relied on dog-whistling the idea of race-based citizenship to corral a base of white voters for generations. The e-mails published this week identify Miller as the most recent runner in the GOP’s relay advancing the baton of pro-white, exclusionary national politics.

In Ian Haney López’s book Dog Whistle Politics, the University of California at Berkeley law professor describes Republican race-baiting as an open secret. “Republicans,” he writes, “rely on racial entreaties to help win elections.” López cites a 2010 speech by former Republican National Committee chairman Michael Steele, admitting that “for the last 40-plus years we had a ‘Southern Strategy’ that alienated many minority voters by focusing on the white male vote in the South.” He recounts a 2005 speech from another former RNC chairman, Ken Mehlman, who confessed the GOP has strived “to benefit politically from racial polarization” for decades. This Southern Strategy of subtly appealing to white voters’ racial animus was infamously summarized by Republican strategist Lee Atwater, adviser to Ronald Reagan and George H. W. Bush:

You start out in 1954 by saying, “Nigger, nigger, nigger.” By 1968 you can’t say “nigger”—that hurts you, backfires. So you say stuff like, uh, forced busing, states’ rights, and all that stuff, and you’re getting so abstract. Now, you’re talking about cutting taxes, and all these things you’re talking about are totally economic things and a byproduct of them is, blacks get hurt worse than whites.… “We want to cut this,” is much more abstract than even the busing thing, uh, and a hell of a lot more abstract than “Nigger, nigger.”