Jennifer Palmieri was communications director for Hillary Clinton’s presidential campaign.

I know how to be a gracious loser.

I could have let it go last week when Kellyanne Conway, Donald Trump’s campaign manager, challenged me to look her in the eye and say she ran a campaign that gave white supremacists a platform. I considered for a split second. I knew you were supposed to be gracious when you come for the post-election forum at Harvard’s Kennedy School of Government. But I decided this was a year where normal rules don’t apply. Speaking the truth was more important.

“It did. Kellyanne, it did,” I told her. It’s just a fact. Trump winning the election doesn’t change that. To my mind, his win makes it all the more important that the truth be acknowledged.

High-level aides to both the Clinton and Trump campaigns became involved in a heated exchange Dec. 1, during a post-election forum sponsored by Harvard University’s Kennedy School of Government. (Harvard University’s Kennedy School of Government)

My colleagues and I from the Hillary Clinton campaign knew what we were likely to face from the Trump side at the Harvard University event and thought hard about our obligations as representatives of the losing side in this most unconventional of years — particularly when our candidate actually won the popular vote by a large margin. As I like to note, Clinton received more votes for president than any white man in U.S. history.

Our candidate gave us a good model to follow. She had the grace to call Trump on election night to congratulate him and concede. But in her concession speech she also challenged all of us to defend our rights and principles under the Constitution — rights and principles that she and many of the people who voted for her feared could be under threat in a Trump presidency. The campaign has ended, and we accept that Trump won. But we are not laying down our principles or abandoning our supporters. That’s the frame of mind I brought to Harvard.

A good bit of the post-election analysis has centered on what our campaign should have done differently. That’s appropriate. We should think long and hard about why we lost. Trust me, we have.

But it’s also important for the winners of this campaign to think long and hard about the voters who rejected them. I haven’t seen much evidence of such introspection from the Trump side. That’s concerning.

I don’t know whether the Trump campaign needed to give a platform to white supremacists to win. But the campaign clearly did, and it had the effect of empowering the white-nationalist movement.

Trump provided a platform by retweeting white nationalists — giving their views an audience of millions. Views previously relegated to the darkest corners of the Internet also had a platform on Breitbart, the website of Trump campaign chief executive Stephen K. Bannon. “Before Trump, our identity ideas, national ideas, they had no place to go,” said Richard Spencer, president of a white-nationalist think tank that held a post-election conference in Washington. Former Ku Klux Klan leader David Duke said this fall, “The fact that Donald Trump’s doing so well, it proves that I’m winning.”

At Harvard, some on the Trump team crowed that we in the Clinton campaign and those in the press were foolish because we took Trump’s words “literally.” That’s right. We did. You should take a candidate for president’s words literally. You know who else took his words literally? White supremacists. The white supremacists who lauded Trump with cries of “Hail, Trump!” Duke, who expressed confidence that Trump’s decision to make Bannon his chief strategist meant Duke’s ideology would have a prominent place in the West Wing. The students who mocked Hispanic athletes with chants of “build that wall.” The man in New York City who threatened the off-duty female Muslim police officer last weekend.

It’s also true that many of the more than 65 million people who voted for Clinton took Trump’s words literally. Many of our supporters were sincerely frightened by his campaign’s embrace of the alt-right. Hispanic families who voted for Clinton believe Trump will deport their parents or siblings because he said he would. Muslim supporters fear they will not be welcome in their own country because of Trump’s proposed Muslim ban. Mothers and fathers of both parties supported Clinton because they didn’t want their children growing up in an America where women and girls don’t feel respected by their own president.

Whether Trump intended for any of these people — both those who were energized and those who were repelled — to take his words literally or not, they did. That has already had real-life consequences that our new president must own up to. That’s why what he said during the campaign matters. That’s why everything he says matters.

If we are not to take Trump’s words literally, he needs to explain what he does mean. The Trump team likes to tell Clinton supporters “hashtag ‘he’s your president.’ ” But this isn’t a one-way street. If Trump expects the Americans who did not vote for him to accept him as president, he needs to show that he accepts all of them as Americans. He needs to show that he understands their concerns and hears their fears.

I suggest he and his team try “hashtag ‘we are all Americans.’ ” We all have a role to play here. But it’s the winner who carries the burden of taking the lead in uniting the country. It’s the burden of leadership. It’s the burden of being the president of the United States.