Donald Trump is mainstreaming hate. That was the central message of Hillary Clinton’s speech last week in Reno, Nev., where she detailed Trump’s record of stoking racism and conspiracy theories. “From the start,” she declared, “Donald Trump has built his campaign on prejudice and paranoia.”

Clinton certainly had a point. Even before the start of his campaign, it was Trump’s disgraceful crusade to “prove” that President Obama was not actually born in the United States that laid the foundation for his victory in the Republican primaries. His most despicable statements of the election — from calling Mexican immigrants “rapists” to promoting the lie that “thousands” of Muslims in New Jersey celebrated the Sept. 11 attacks — have only cemented his hero status among bigots and cranks who were previously relegated to the fringes of society.

While past Republican nominees have flirted with extremists, none has embraced or encouraged them so openly. As Clinton pointed out, Trump has brought out of the online shadows an emerging movement known as the “alt-right.” Despite lacking clear leaders or a cohesive ideology, the alt-right “is bound together by common enemies: women, minorities, immigrants and national institutions that, by their worldview, threaten the freedom of white men with the toxic sword of political correctness,” Jack Smith IV writes. Notably, in his former role as the chairman of Breitbart Media, Trump’s new campaign chief executive Stephen Bannon boasted, “We’re the platform for the alt-right.”

Trump has not merely given voice to the visceral hatred in our midst. With his brazen lies and his childish taunts, Trump has also effectively given permission for people to say virtually anything in public without regard for facts or fear of repercussions. This could have a lasting impact on our public discourse regardless of how Trump fares in November.

Already, Trump has debased the political debate. As Felix Salmon observes, Trump’s outrageous behavior “tends to render invisible severe and important policy distinctions,” which is a problem especially in state and local races where Trump is not one of the choices. “This year, the effect is likely to be felt strongly in down-ticket races, where Democratic and Republican candidates are finding it incredibly hard to cut through the noise of the presidential race and to have substantive debates,” he writes.

At a rally in Jackson, Miss., Republican presidential nominee Donald Trump called Democratic foe Hillary Clinton a "bigot" and said that she would do "nothing" for African Americans and Hispanics. (The Washington Post)

Meanwhile, Trump’s impact is also increasingly apparent among our children. In April, the Southern Poverty Law Center released a report finding that many kids “have been emboldened by the divisive, often juvenile rhetoric in the campaign,” with teachers witnessing among their students “an increase in bullying, harassment and intimidation.” At the same time, members of the alt-right have turned online bullying and harassment into something of a sport; their unrelenting abuse of “Saturday Night Live” star Leslie Jones is the latest example in an ugly trend.

Some have expressed hope that, in the event that Trump loses, Trump-ism will go down with him. That may be wishful thinking. Even a landslide seems unlikely to deter Trump’s most rabid fans, especially if he continues to claim that the election was “rigged.” In addition, there are credible rumors that Trump’s fallback plan is to establish a media presence — possibly working with Bannon and former Fox News head Roger Ailes — that could compete with Fox News for supremacy on the right.

Regardless of the outcome, there is no reason to believe that a Trump defeat would reverse the damage his campaign has already done, especially its impact on how young people view the political process. Millennial voters, who were so energized by Bernie Sanders, are rejecting Trump in overwhelming numbers. But they could ultimately decide to reject politics altogether — both in 2016 and for years to come. With U.S. voter turnout hovering at just more than 50 percent, this would be devastating for our democracy.

Over the coming weeks, the election will only become more brutal. As Trump scorches the earth with his vitriolic tweets and verbal assaults, Clinton should guard against the cynicism his campaign has inspired by making a concerted effort to reach the millions of young people whose voices still need to be heard. And no matter what the polls say, Clinton and her supporters should remember that the danger in this election is not just that Trump could win. It’s that — win or lose — he could poison our politics for a generation.

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