The Editorial Board

USA TODAY

In the not so distant past, politicians would reach racist voters through what are sometimes called “dog whistle” comments. These are cautious, subtle statements that most people hear only as policy mumbo jumbo — criticizing affirmative action, say, or activist judges — but which others hear as reaffirmation of their bigoted worldviews.

How utterly different things are now, with the president of the United States deploying the oldest racist trope in the book by calling on four congresswomen of color to go back to where they came from. (Never mind that all four are U.S. citizens, and three were born in the USA.)

In so doing, Donald J. Trump is replacing the dog whistle with a bullhorn. He is all but declaring: I am a racist. I will advocate racist policies. I will redefine the Republican Party of Abraham Lincoln, Teddy Roosevelt and Ronald Reagan as the party of white grievance against a changing America.

To anyone who has been paying attention, Trump’s offensive comments, tweeted before a Sunday golf outing, were shocking but not surprising. Trump has trafficked in bigotry throughout his career in business and politics.

Way back in 1973, the Justice Department sued him and his father for systematically discriminating against blacks in housing rentals. Trump called for the death penalty for minority youths accused in the 1989 “Central Park Five” case. For five years, he fanned the absurd “birther” movement that falsely questioned the legitimacy of the first African-American president, Barack Obama.

Trump launched his presidential campaign by whipping up resentment against Muslims, Mexicans and migrants. He characterized poorer countries run by blacks as “s---holes.” After a deadly neo-Nazi rally in Charlottesville, Va., he said there were “very fine people” on both sides. And so on.

Responding to Trump’s stink bombs can be exhausting, and it’s tempting to just ignore them, especially when he’s trying to change the subject from topics such as migrant children locked up in detention centers, sex-trafficking charges against former friend Jeffrey Epstein and deportation raids that didn’t live up to their advance billing.

In this case, Trump undoubtedly also saw an opportunity to exploit divisions in the Democratic Party between old guard leaders such as Nancy Pelosi and the “squad” of four outspoken first-term representatives: Alexandria Ocasio-Cortez, Ilhan Omar, Ayanna Pressley and Rashida Tlaib.

Yet some comments are too offensive to be ignored, and Trump is making it impossible to overlook his racism in all its grim venality. As if his original schoolyard tweet calling on the four congresswomen to go away wasn’t enough, the president — who campaigned for office painting a dark picture of “American carnage” — dug himself in deeper Monday by saying that they hated their country. “If you’re not happy here, you can leave,” he added for good measure.

For Democrats, Trump’s attacks are likely to serve as a unifying force between the establishment and insurgent wings of the party.

For Republicans, Trump presents a Hobson’s choice of jumping into the moral cesspool with him, or facing the wrath of Republican primary voters who’ve convinced themselves that Trump is worthy of support.

As of Monday evening only a handful of Republican members of Congress had spoken out against Trump, just as only a handful objected when he violated the Constitution to divert money without an appropriation, or when he attacked judges and prosecutors he did not like.

It is time for the party to stand up to say enough is enough. Trump is not only doing harm to the institutions of government and to the fabric of society, he is taking a proud Republican Party down a hole it will be hard to get out of.

As the percentage of voters who are members of racial and ethnic minorities passes 30%, quite possibly next year, and then 40% in the years beyond, how is the GOP going to appeal to them with such a blot on its record?

At least Trump has made his true colors abundantly clear. Now it’s up to his fellow Republicans and voters everywhere to demonstrate that racism is disqualifying, that the sentence “he’s a racist, but ...” has no place in American politics.

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