When President Reagan spoke to the nation upon being nominated for re-election at the 1984 Republican National Convention, he went out of his way to declare, “In the party of Lincoln, there is no room for intolerance. … Many people are welcome in our house, but not the bigots.”

Now there was a reason Reagan felt compelled to draw such a line. Four months earlier, he received an endorsement from the Ku Klux Klan, as he had in 1980. Reagan rejected the endorsement each time, but in 1984 he received some criticism for not doing so immediately.

Reagan had other awkward episodes regarding race. In late 1981, he directed the Justice Department to end its legal defense of the IRS’s right to deny federal tax exemptions to Bob Jones University, which at the time banned interracial dating and marriage. But after much blowback, Reagan recalibrated his stance, proposing legislation that would codify the IRS’s authority to deny the exemptions and eliminate legal ambiguity. (The bill failed but the Supreme Court sided with the IRS.)

And in 1983, Reagan signed legislation establishing a national holiday in honor of the Rev. Martin Luther King Jr. However, before the bill reached his desk, he expressed reluctance, preferring a “day of recognition” short of a holiday. And he sympathized with the request of a senator to open King’s sealed records and examine whether he was a communist.

Whether you think Reagan was motivated by sincerity or political calculation, the fact is when given the opportunity to directly address his party and the broader electorate about bigotry, on the biggest possible stage, Reagan spoke without equivocation. A tone was set at the top that there were some lines that should not be crossed.

Reagan’s Republican successors walked similar tightropes while trying to keep the GOP from being tainted by racism. In 1988, George H.W. Bush may have trafficked in racial wedge politics during his successful presidential campaign with the “Willie Horton” attacks on Gov. Michael Dukakis. But in 1991, when former Ku Klux Klan leader David Duke was carrying the Republican banner in the race for Louisiana governor, Bush slammed Duke as a racist and effectively ceded the election to the Democrats.

On Oct. 10, 2008, at a town-hall event, Sen. John McCain refused to coddle the racist sentiments uttered by his supporters about the first African-American presidential nominee in U.S. history. When a woman said to McCain, “I can’t trust Obama. I have read about him. … He’s an Arab,” the Republican candidate had heard enough. He cut her off, took the microphone away and said, “No, ma’am. He’s a decent family man, citizen, who I just happen to have disagreements with on fundamental issues.”

And in 1996, Republican presidential nominee Bob Dole was hitting President Clinton hard on “illegal immigration.” But, like Reagan, Dole deemed it necessary at his nomination convention to clarify that his stance against undocumented workers was not tantamount to bigotry: “A family from Mexico who arrived this morning legally has as much right to the American Dream as the direct descendants of the Founding Fathers. … If there's anyone who has mistakenly attached themselves to our party in the belief that we are not open to citizens of every race and religion … the exits which are clearly marked are for you to walk out of as I stand this ground without compromise.”

Those exits are no longer clearly marked.

On Saturday, Trump refused to call out the white supremacy and domestic terrorism in Charlottesville, Va., by name. He casually pinned the “hatred, bigotry and violence” on “many sides.” And he signaled common cause with the bigoted protesters who came to stop the removal of a Confederate memorial, when he urged all to “cherish our history.”

(By the time this column is published, I would not be surprised if Trump delivered some light criticism of the white supremacists, hoping to quell the attacks on him. But the intended signals have already been sent.)

One could argue that Trump, unlike some of his Republican predecessors, is refreshingly lacking in subtlety about pandering to bigots. Past Republican operatives have spoken bluntly on the subject, such as Richard Nixon’s adviser Kevin Phillips. He told the New York Times in 1970: “From now on, the Republicans are never going to get more than 10 to 20 percent of the Negro vote and they don't need any more than that. . . . The more Negroes who register as Democrats in the South, the sooner the Negrophobe whites will quit the Democrats and become Republicans. That's where the votes are.”

And Republicans were hardly alone in trying to woo “Negrophobe whites” in the post-Civil Rights Act era. George McGovern pledged in 1972 not to give a dime in welfare to “those who don’t want to work.” During the 1976 campaign, Jimmy Carter defended working-class whites “who are trying to maintain the ethnic purity of their neighborhoods.” And in 1992, Bill Clinton had his “Sister Souljah” moment, in which he humiliated the Rev. Jesse Jackson.

Back then, Democrats could employ these maneuvers without losing African-American voters. Today, America is more diverse, and Democratic base voters, regardless of racial background, are holding their politicians to higher standards. There were no “Sister Souljah” moments in Hillary Clinton’s 2016 campaign, and there likely will never be one again in a Democratic campaign.

Sensing that these demographic changes will soon affect the GOP as well, forward-thinking Republicans have been trying to upgrade the party. They recognize that reactionary views on issues such as immigration, race, sexual orientation and gender identity would fatally contain the party’s growth. The Republican National Committee, under the supervision of then-Chairman Reince Priebus, reacted to Mitt Romney’s presidential defeat in 2012 with an “autopsy” that cited a need to “expand and diversify the base of the Republican Party” because “[t]he nation’s demographic changes add to the urgency of recognizing how precarious our position has become.”

Trump’s victory temporarily sidelined those voices, proving that the predominantly white, social conservative Republican base still has a little juice left in it. But the voices of inclusion are beginning to speak up again.

Two weeks ago, Sen. Jeff Flake published a book that counseled his colleagues “to speak out if the president ‘plays to the base’ in ways that damage the Republican Party’s ability to grow and speak to a larger audience.” On Saturday, many Republicans appeared to take Flake’s advice, with not only McCain reprising his role as a voice of conscience, but also rock-ribbed conservatives like Sen. Ted Cruz and Sen. Orrin Hatch distancing themselves from Trump’s rhetoric and condemning white supremacism and domestic terrorism by name.

That’s a start. The next step is to echo Reagan, and say with crystal clarity that there is no room for bigots in the Republican Party.

Such a declaration could be based on political conviction or political calculation. But failure to draw a firm line against hate risks allowing Trump to define the party long after he’s gone from the White House, and long after his coalition has demographically withered.