In 2017, The New York Times reported on a meeting between Trump and several members of his cabinet in which he raged against foreign visitors to the United States. Citing a memo from Stephen Miller, the president’s chief immigration hard-liner, Trump complained about the pending arrival of thousands of people from Muslim and predominantly African nations. They “all have AIDS,” Trump reportedly said, about immigrants from Haiti. As for Nigerians? Once they saw America, they would never “go back to their huts.”

All of this was separate from the president’s remarks on what he famously called “shithole countries” — those came the next year, when he found a fresh way to articulate his racist vision of immigration policy, where white Europeans are welcome and nonwhites are not.

Which is to say that it does not matter that Nigeria isn’t much of a national security threat or that Nigerians are among the most successful immigrants to the United States, surpassing native-born Americans in income and educational attainment. What matters is that they’re black and African and, for Trump, at the bottom of a racial hierarchy.

I’ve written before about the 1924 Immigration Act, also known as the Johnson-Reed Act, which codified a decade’s worth of nativist hysteria into law. It followed the Immigration Act of 1917, which imposed literacy tests on new immigrations and barred immigration from the Asia-Pacific region, and the Emergency Quota Act of 1921, which established the first per-country percentage limits on the number of immigrants to the United States. The 1924 act was the harshest. It was also the most far-reaching. Meant to reduce immigration from Southern and Eastern Europe, it also defined the American nation in explicitly racial terms.

The quota system established by Johnson-Reed, the historian Mae Ngai writes, “subtracted from the total United States population all blacks and mulattoes, eliding the difference between the ‘descendants of slave immigrants’ and the descendants of free Negroes and voluntary immigrants from Africa. It also discounted all Chinese, Japanese and South Asians as persons ‘ineligible to citizenship,’ including descendants of such people with American citizenship by native birth.”