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When some presidents leave office, politicians and political thinkers jockey to be their intellectual heirs. Even Ronald Reagan, a Republican, claimed the legacy of John F. Kennedy. Even Barack Obama, a Democrat, claimed the legacy of Reagan.

If Donald Trump loses this fall, few will be in a hurry to claim his legacy. Commentators on the left and in the center—and even some on the right—will compete instead to tar their foes with it. For people across a broad ideological terrain, Trumpism will be less an attractive political philosophy than a term of abuse.

The best precedent is McCarthyism, which has become a synonym for hysterical intolerance. Joseph McCarthy, like Trump, built his political career on demagoguery, intimidation, and a cult of personality—not tangible achievements or coherent ideas. And as the psychology professor Dan P. McAdams has observed, “When narcissists begin to disappoint those whom they once dazzled, their descent can be especially precipitous.” More than a half century after the senator from Wisconsin died, progressives accuse conservatives of McCarthyism, and vice versa. But few embrace the label themselves. Especially if Trump is badly defeated in November—a distinct possibilityTrumpism too will likely be used primarily as an epithet.

What the epithet means, however—and to whom it applies—is already being contested. On one side sit people who define Trumpism as a form of intolerance, a disrespect for the rules that undergird American democracy. On the other sit people who define Trumpism as a form of oppression, a manifestation of the fact that the rules undergirding American democracy are saturated with racial, gender, and class bias. The debate between these two views will shape the relationship between the activist left and the political center for years to come.

You can see the outlines of the first anti-Trump position—Trumpism as intolerance—in last week’s much-discussed “Letter on Justice and Open Debate,” published by Harper’s Magazine. The authors call Trump “a real threat to democracy” and an ally of “the forces of illiberalism.” But they worry that illiberal tendencies are also growing on the left, which is creating “its own brand of dogma or coercion” that threatens “democratic inclusion.” The authors don’t claim that leftist intolerance poses as grave a threat as the populism of the right. But the implication is that Trumpism is not simply a right-wing phenomenon. It’s a form of intolerance—a willingness to violate the norms of liberal-democratic fair play—that transcends ideological divides. As Yascha Mounk, one of the letter’s signers and an Atlantic contributing writer, argues in an introduction to his new journal, Persuasion, “The primary threat to liberal democracy is posed by the populist right” but the “values of a free society” also “are losing their luster among significant parts of the left.”

Mounk and others of similar mind are proposing an updated version of what Arthur M. Schlesinger Jr. in 1949 famously called the “vital center,” in a book of the same name. Schlesinger’s argument was that both the fascist right and the communist left shared common totalitarian features. It was thus necessary for liberals and conservatives who believed in a free society to recognize that, whatever their policy differences, they shared a broad ideological camp: the vital center. Substitute Trumpism for totalitarianism, and you can detect the same impulse in the work of those writers who define Trumpism as a species of intolerance that manifests itself on both the left and the right.

In contrast, influential progressives are defining Trumpism not as intolerance but as oppression, and thus, necessarily, the province of those who enjoy racial, gender, or class privilege. After the Harper’s letter was published, another group of commentators wrote a response titled “A More Specific Letter on Justice and Open Debate.” This group—“started by journalists of color with contributions from the larger journalism, academic and publishing community,” according to the letter—accused the Harper’s signatories of failing to “deal with the problem of power: who has it and who does not.” The Harper’s letter never uses the words Black, white, brown, or trans. The response (which, granted, is longer) uses them at least four dozen times. It claims that the Harper’s signers are using the supposed intolerance of members of historically oppressed groups as an excuse for their own “unwillingness to dismantle systems that keep people like them in and the rest of us out.”

In The Atlantic, Ta-Nehisi Coates famously described Trump’s politics as white supremacy made evident because of the election of a Black president. Although the writers of the “More Specific Letter” don’t mention Trump by name, they’re building on Coates’s argument: Trumpism is the brutal manifestation of inherited power. Thus, the notion that it could be a malady that transcends lines of class, race, gender, and ideology—expressed not only by Republican politicians but by people of color in newsrooms and on campuses—is nonsense. As the writer Jeet Heer has argued, Trumpism is the culmination of the GOP’s decision to make itself white America’s vehicle for opposing racial equality. So there cannot be a “Trumpism of the left.”

Today, the argument about the meaning of Trumpism is taking place in intellectuals’ letters. But if Trump loses, it will migrate to Washington. Democrats insistent on dramatic change will collide with conservatives able to block it. Progressives will then demand, as they have already begun to do, structural changes that would let them override the right’s veto. Such demands could take the form of sweeping new executive actions, alterations to the structure of the Supreme Court, efforts to abolish the filibuster, and moves to grant statehood to Washington, D.C., and Puerto Rico. Some of the people who define Trumpism as intolerance will view such moves as a progressive form of Trumpism—that is, as an assault on the rules of fair play. In 2018, Obama’s former White House counsel Bob Bauer warned that if liberals expanded the size of the Supreme Court, they would “emulate President Trump’s contempt for democratic institutions and the rule of law.” If Trump’s Democratic successor imposes policies of “the far left via executive order,” my colleague David Frum argued last year, it will be a sign that “neither side abides by the rules of democracy.”

The progressives who define Trumpism as oppression will reject these claims as absurd. They will argue that certain aspects of America’s system of government undemocratically entrench the privilege of historically dominant groups; by this logic, structural changes that allow progressives to bypass conservative opposition constitute not an attack on democracy but the removal of barriers to it. Making Washington, D.C., a state, The Week’s Ryan Cooper has argued, would enfranchise 700,000 people—almost half of them Black—“who are currently treated like quasi-colonial subjects.” Eliminating the filibuster, Cooper maintains, would end a practice that, historically, has been “primarily used by racists to stop civil rights legislation.”

Schlesinger’s vision of a vital center—composed of liberals and conservatives who made common cause against both the undemocratic left and the undemocratic right—dominated American politics in the years after World War II because there was no leftist movement powerful enough to challenge it. In the late 1960s—under pressure from the anti-war movement, the feminist movement, and the movement for Black freedom—it lost its intellectual hegemony. The problem for Schlesinger’s successors today is that they are trying to constitute a new vital center at a time when the activist left is strong enough to challenge their control over the terms of debate. One way that challenge will unfold is through an effort at ideological guilt by association, in which each side will accuse the other of being Trumpism’s rightful heir.

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