Jeenah Moon / Reuters

On Monday night, Alexandria Ocasio-Cortez declared in an Instagram video that “the United States is running concentration camps on our southern border.” The following morning, Liz Cheney tweeted, “Please @AOC do us all a favor and spend just a few minutes learning some actual history. 6 million Jews were exterminated in the Holocaust. You demean their memory and disgrace yourself with comments like this.” After that, the fight was on.

On its face, the fight was about using concentration camp outside the context of the Holocaust. In a subsequent tweet, Ocasio-Cortez linked to an Esquire article noting that the term pre-dates World War II. It quoted the historian Andrea Pitzer, who defines concentration camp as the “mass detention of civilians without trial.” To Ocasio-Cortez’s critics, this was too cute by half. Whatever the term’s historical origins or technical meaning, in American popular discourse concentration camp evokes the Holocaust. By using the term, they argued, the representative from New York was equating Donald Trump’s immigration policies with Nazi genocide, whether she admitted it or not.

But whether you believe Ocasio-Cortez’s terminology was appropriate or offensive, the deeper question is why it provoked such a ferocious debate. The answer: Because for the first time in decades, the left is mounting a serious challenge to American exceptionalism.

American exceptionalism does not merely connote cultural and political uniqueness. It connotes moral superiority. Embedded in exceptionalist discourse is the belief that, because America has a special devotion to democracy and freedom, its sins are mostly incidental. The greatest evils humankind has witnessed, in places such as the Nazi death camps, are far removed from anything Americans would ever do. America’s adversaries commit crimes; America merely stumbles on its way to doing the right thing. This distinction means that, in mainstream political discourse, the ugliest terms—fascism, dictatorship, tyranny, terrorism, imperialism, genocide—are generally reserved for phenomena beyond America’s shores.

A half century ago, Vietnam so radicalized the American left that it seriously challenged these semantic boundaries. Exceptionalist assumptions underlay America’s rationale for war: The North Vietnamese were Communists; Communists were totalitarians; totalitarians committed aggression, as Hitler had in the 1930s. Thus, Hanoi was the aggressor in Vietnam, not the freedom-loving United States.

The anti-war movement inverted this moral logic. In the 1969 book that helped make him famous, American Power and the New Mandarins, Noam Chomsky argued that “by any objective standard, the United States has become the most aggressive power in the world.” Invoking some of the most notorious fascist crimes of the 1930s and 1940s, the anti-war leader Jerry Rubin declared, “Vietnam is the Guernica, the Rotterdam, and the Lidice of the 1960s.” This antiexceptionalist discourse—which denied America’s moral superiority over the adversaries it had long contrasted itself against—even penetrated the Democratic Party. In 1971, George McGovern—who the Democrats would nominate for president the following year—called Richard Nixon’s bombing of Southeast Asia “the most barbaric act committed by any modern state since the death of Adolf Hitler.”

But when the anti-war and other protest movements of the 1960s faded, so did their challenge to exceptionalist language. By the 1980s, Democrats were playing catch-up to Ronald Reagan’s flag-waving patriotism. Exceptionalism was further bolstered in the 1990s, when the fall of the Soviet Union and the seemingly global embrace of American-style democracy and capitalism appeared to reaffirm the fundamental superiority of America’s political system. During the Barack Obama years, questioning American exceptionalism was considered a career-imperiling transgression. When Republicans questioned his commitment to the creed, Obama in 2014 replied, “I believe in American exceptionalism with every fiber of my being.”   

In recent years, however, a resurgent left fueled by an influx of Millennial voters has launched a new challenge to exceptionalist discourse. Partly, it’s because a higher percentage of Millennials are people of color, who generally look more skeptically on America’s claims of moral innocence. Partly, it’s because the financial crisis has cast doubt on whether America’s economic model is preferable to those practiced in other nations. Younger Americans—a majority of whom embrace “socialism”—believe it’s not. Most of all, the challenge to exceptionalism is a response to Trump.

The generational divide is evident in polls. A 2017 Pew Research Center survey found that Americans over the age of 65 were 37 points more likely to say the “U.S. stands above all other countries in the world” than that “there are other countries that are better than the U.S.” Americans under 30 split in the opposite direction. By a margin of 16 points, they said some other countries were better. A similar divide separates liberals and conservatives. While conservatives affirm America’s superiority by a margin of almost 10 to one, liberals reject it by more than two to one.

These numbers help explain why left-leaning politicians and commentators up and down the age spectrum have grown more willing to challenge the linguistic conventions that traditionally reserved certain epithets for America’s adversaries. A few years ago, commentators rarely evoked the specter of American “authoritarianism.” Now it’s commonplace. Books such as George Orwell’s 1984 and Sinclair Lewis’s It Can’t Happen Here hit the best-seller lists after Trump’s election. Anti-Trump activists began calling themselves “the Resistance,” a term that, by evoking the French or Polish Resistance to Nazism, implies opposition to a tyrannical regime in the United States.

With his embrace of foreign authoritarians and his cultivation of conservatism’s xenophobic and racist fringes, Trump has become a galvanizing figure for the left, which for the first time since the 1960s has begun regularly evoking the specter of American “fascism.” Ocasio-Cortez refers to Trump’s “fascist presidency.” In a video last year, Bernie Sanders quoted a scholar who accused Trump of “flirting with fascism in the open, in broad daylight.” This week, the former Obama speechwriter Ben Rhodes described parts of Trump’s kickoff reelection speech as “indistinguishable from fascist rhetoric.”

The new prominence of the “antifa” movement also testifies to this linguistic shift. The term—which is shorthand for “antifascist activists”—comes from Europe, where communists and anarchists waged street battles against fascists in the 1930s, and against neo-Nazi skinheads in the 1970s and 1980s. But when anti-skinhead activists began Americanizing the movement in the 1980s, many adapted the term: “antiracist action.” Fascism didn’t seem like an American problem. That’s no longer the case. Leftist street activists now embrace the term antifa, and the movement has grown dramatically under Trump.

In their antiexceptionalist turn, Trump-era progressives aren’t just sounding alarms about authoritarianism and fascism in the United States today; they’re also reinterpreting the American past. New scholarship has, for instance, muddied the distinction between German Nazism and early-20th-century American white supremacy. The Yale Law School Professor James Whitman’s 2017 book, Hitler’s American Model: The United States and the Making of Nazi Race Law, has gained favorable attention in The New Yorker, The New York Times, The Washington Post, and The Atlantic. After then–Attorney General Jeff Sessions declared that last year’s Pittsburgh synagogue shooting was “utterly repugnant to the values of this nation,” my Atlantic colleague Adam Serwer excavated the work of World War I–era racial theorists such as Madison Grant to show that the “seed of Nazism’s ultimate objective—the preservation of a pure white race, uncontaminated by foreign blood—was in fact sown with striking success in the United States.”

This willingness to equate American white supremacy with the barbarism that occurs in other countries has also shaped the way the left describes terrorism. In past decades, the term was reserved almost exclusively for America’s enemies, particularly in the Muslim world. Now it’s become common, not only among leftist commentators but among Democratic politicians, to apply the term to violence committed by native-born white Americans. “America’s greatest terrorist threat?” asked Representative Tom Malinowski of New Jersey in an op-ed last month. “White supremacists.”

Ocasio-Cortez’s comment about concentration camps is only the latest example of this broad challenge to American exceptionalism. She didn’t claim that Trump’s detention centers are the equivalent of Auschwitz. But she denied that America is a separate moral category, so inherently different from the world’s worst regimes that it requires a separate language. On Tuesday night she retweeted the actor George Takei, who wrote, “I know what concentration camps are. I was inside two of them, in America.” This was another act of linguistic transgression. When remembering the detention of Japanese Americans during World War II, Americans have generally employed the term internment camps—largely, the historian Roger Daniels has argued, to create a clear separation between America’s misdeeds and those of its hated foes.

Ocasio-Cortez and others on the Millennial-led left are challenging that separation now. They are challenging not only the physical and legal barriers that Trump is erecting against immigrants entering the United States, but also the conceptual barriers that American exceptionalism erects against seeing the United States as a nation capable of evil. And for Ocasio-Cortez’s critics, removing those ideological barriers is every bit as frightening as allowing migrant caravans to pass unimpeded across the Rio Grande.

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