Another revealing moment came in 1989, when New York City was convulsed by the “Central Park jogger” case, a rape and beating of a young white woman. Five black and Latino teenagers were arrested.

Trump stepped in, denounced Mayor Ed Koch’s call for peace and bought full-page newspaper ads calling for the death penalty. The five teenagers spent years in prison before being exonerated. In retrospect, they suffered a modern version of a lynching, and Trump played a part in whipping up the crowds.

As Trump moved into casinos, discrimination followed. In the 1980s, according to a former Trump casino worker, Kip Brown, who was quoted by The New Yorker: “When Donald and Ivana came to the casino, the bosses would order all the black people off the floor. … They put us all in the back.”

In 1991, a book by John O’Donnell, who had been president of the Trump Plaza Hotel and Casino in Atlantic City, quoted Trump as criticizing a black accountant and saying: “Black guys counting my money! I hate it. The only kind of people I want counting my money are short guys that wear yarmulkes every day. … I think that the guy is lazy. And it’s probably not his fault, because laziness is a trait in blacks. It really is, I believe that. It’s not anything they can control.” O’Donnell wrote that for months afterward, Trump pressed him to fire the black accountant, until the man resigned of his own accord.

Trump eventually denied making those comments. But in 1997 in a Playboy interview, he conceded “the stuff O’Donnell wrote about me is probably true.”

The recent record may be more familiar: Trump’s suggestions that President Obama was born in Kenya; his insinuations that Obama was admitted to Ivy League schools only because of affirmative action; his denunciations of Mexican immigrants as, “in many cases, criminals, drug dealers, rapists”; his calls for a temporary ban on Muslims entering the United States; his dismissal of an American-born judge of Mexican ancestry as a Mexican who cannot fairly hear his case; his reluctance to distance himself from the Ku Klux Klan in a television interview; his retweet of a graphic suggesting that 81 percent of white murder victims are killed by blacks (the actual figure is about 15 percent); and so on.

Trump has also retweeted messages from white supremacists or Nazi sympathizers, including two from an account called @WhiteGenocideTM with a photo of the American Nazi Party’s founder.