“A Night at the Garden” is a seven-minute documentary film composed entirely of archival footage that is, in its way, as chilling and disorienting to watch as the most inventive full-length horror movie. The film, which is nominated for an Oscar in the Documentary Short category, chronicles the night in February, 1939, when twenty thousand American men, women, and children gathered at Madison Square Garden for an event billed as a “Pro-American Rally.” In the opening minutes, the signifiers seem scrambled, as though in a nightmare. A banner of George Washington hangs at the back of the stage; there are American flags everywhere and excited kids dressed in what might be scouting uniforms. But people in the audience are giving the stiff-armed Hitler salute, and the speaker is Fritz Kuhn, the head of the German-American Bund, a national organization that supported the Nazi Party.

But even more unnerving than the strangeness of the spectacle is the creeping sense of familiarity it evokes. Kuhn’s snarky excoriation of the “Jewish-controlled” press, his demand “that our government shall be returned to the American people who founded it,” and even the idolatry of the Founding Fathers all have their echoes in far-right politics today. No moment in the film seems more redolent of our current demagogue’s MAGA rallies than the one in which a protester scrambles onto the stage—he was Isadore Greenbaum, a twenty-six-year-old plumber’s helper from Brooklyn—and is promptly tackled and pummelled by Kuhn supporters, amid appreciative laughter and hooting from the crowd.

One advantage to living through Trumpism is that it has compelled a reckoning with aspects of our country’s past that, for a long time, many Americans preferred not to acknowledge. Donald Trump’s encouragement of white supremacists accelerated the examination of why we were still living among so many monuments to the Confederacy. The work undertaken by historians and activists to document America’s full, horrifying legacy of lynching acquired a new urgency. In April of last year, a memorial opened in Montgomery, Alabama, commemorating the deaths, by racial terror, of some forty-four hundred African-Americans between 1877 and 1950. As the project’s founder, the lawyer and activist Bryan Stevenson, once told a group of volunteers, “We talk a lot about freedom. We talk a lot about equality. We talk a lot about justice. But we’re not free. There are shadows that follow us.”

As a result of such efforts, more white Americans may be facing certain fundamental facts: that America’s deepest form of exceptionalism is the poison at its root that is slavery, and that the ways that the country does shine—its multiculturalism and the sturdiness of its democracy to date—have often been threatened by reactionary forces. In his book “Hitler’s American Friends: The Third Reich’s Supporters in the United States,” from 2018, the historian Bradley Hart argues, for example, that in the lead-up to the Second World War “the threat of fascist subversion was very real” in the United States. A mix of German loyalists, garden-variety anti-Semites, would-be spiritual-cult leaders, prominent isolationists such as Charles Lindbergh, corporate interests that hoped to keep doing business with the Nazis, and the hate-spewing (and enormously popular) radio host Father Charles Coughlin did their best to foment nativist sentiment, foster admiration of Hitler, and keep America out of the war. They failed in part because of their own corruption scandals, in part because Hitler had little hope for the mongrel United States and did not offer the aid his U.S. acolytes expected, and in part because reporters and activists exposed and called out these homegrown fascists. (Hart tells the story of one journalist, John C. Metcalfe, a German-born writer for the Chicago Daily Times, “who painstakingly established a false identity over the course of months to infiltrate the Bund and gain the trust of its leadership.”) Ultimately, they were saved from themselves by Pearl Harbor.

This digging into the uglier parts of our past is hard to do, and even harder to absorb, and the lure of rose-colored amnesia has many aiders and abettors. Politically weaponized nostalgia. Fox News-style sanctimony about American history. (Not surprisingly, Fox refused, last week, to air an ad for “A Night at the Garden” with the tagline “It can happen here.”) A President who flaunts his ignorance of American laws by tweeting about “retribution” for the network when Alec Baldwin does his Trump shtick on “S.N.L.” (“You should read the Constitution,” the congressman Ted Lieu, of California, tweeted. “Or get briefed on it.”) A precipitous decline in the number of people studying history. (According to a study released in November by the American Historical Association, the number of undergraduate history majors has fallen over the last decade to its lowest point since the nineteen-eighties—a phenomenon, the study’s author, Benjamin M. Schmidt, notes, that seems to represent not just a “temporary response” to the post-recession job market but “a longer-term rethinking of what majors can do for students.”) The American bias toward optimistic reinvention and the human bias toward ignoring the bad parts of the story, especially when they implicate you.

That’s why we need an approach to history that doesn’t lull and flatter us. We don’t need any more hagiographies of the Founding Fathers or paeans to America’s enduring specialness. To begin to repair our country’s flaws, we have to be clear-eyed about them and unsentimental in our patriotism, and that is actually a hopeful task. As Bryan Stevenson told the Times last year, “People do not want to admit wrongdoing in America, because they expect only punishment. I’m not interested in talking about American history because I want to punish America. I want to liberate America.”