The Washington Post says, as retweeted by Media Professor Dan Gillmor, that

One of Trump's most ugly achievements: People feel freer to make outright racist public comments. https://t.co/aiID94WD4I

— Dan Gillmor (@dangillmor) June 17, 2016

Here's what Washington Post writer Max Ehrenfreund has to say about the Willie Horton ad of 1988 (with emphasis added):

For all its notoriety, the Willie Horton ad probably had little to do with Dukakis's defeat, the political scientist Tali Mendelberg found. Her surveys showed that the Willie Horton advertisement did seem to increase support for George H.W. Bush among racially conservative white Americans initially, but by the election eight weeks later, the spot had no measurable effect in the surveys.

Mendelberg argues that all it took for Democrats to undercut the advertisement's appeal was to point out its racial connotations, as the Rev. Jesse Jackson did a couple of weeks before the election. She believes Jackson's comment revealed that the Willie Horton spot violated an unwritten rule: Race was taboo. Even those white voters with unfavorable views of African Americans became uncomfortable with the advertisement.

There is no such unwritten rule today, if there ever was. A series of recent surveys suggests that racially conservative Americans are open to explicit conversations about race. The data implies that politicians who use explicit, even inflammatory, racial rhetoric will not pay the kind of penalty at the polls that many observers might expect.

Only white, Republican politicians have ever really paid a penalty for "explicit, even inflammatory, racial rhetoric".  Minority politicians have never stopped—see Barack Obama's "“If I had a son, he'd look like Trayvon,”  Eric Holder's "My people" diatribe, and of course, anything at all said by Al Sharpton or Jesse Jackson.

See Why Do Only Whites Lose Jobs Over Racial Remarks? which details the reign of terror white commentators of all kinds have been living under for years, and remember that John Derbyshire was fired for a column that replied to dozens of articles about the "Talk" that black parents give to their kids to stop them from being killed  by white cops for no reason at all.

So if Trump is starting to end this reign of terror, it's one more sign that once again, it's "Morning in America".