When Senator Joseph McCarthy died in 1957, he was one of the biggest failures in American political life, an alcoholic wreck censured by his fellow legislators and treated as a pariah by most in his own party, with his very name a byword for demagoguery and character assassination. “McCarthyism” has become a common—indeed too common—accusation today, wielded across the political spectrum whenever there’s a whiff of overreach.

But if anyone in recent American history is deserving of the term, it would be President Donald Trump, who has called congressional Democrats “treasonous” for not clapping during the State of the Union address and has attempted to purge the FBI and Justice Department of those he sees as disloyal conspirators. “Today’s McCarthy figure is not a mere senator, but the president,” Washington Post columnist Richard Cohen argued on Monday. “Still, the modus operandi is similar. McCarthy railed against communists in government and Trump and his allies inveigh against something called ‘the deep state.’” Another Post columnist, Max Boot, on Monday described Trump as “the second coming of ‘Tail Gunner Joe’” (McCarthy’s nickname).

But Trump’s supporters see the president as a victim of McCarthyism. Fox News Sean Hannity has accused Democratic members of the House Intelligence Committee of using “McCarthyite tactics” in pushing for the declassification of a memo defending the intelligence-court warrants used to investigate Trump campaign associates. The president’s son Donald Trump Jr. tweeted the following on Friday:

He elaborated on this view on Fox News on Saturday. “You see the Democratic senators [saying], ‘This is McCarthyism.’ I’m, like, What? You have a guy screaming, ‘Russia, Russia, Russia’ with no evidence,” he said. “I mean, the irony is ridiculous at this point.” He added that the Democrats are “left of commie right now”—which is exactly the sort of conflation of liberalism with communism that was McCarthy’s rhetorical hallmark. Even the president himself once claimed to be the victim of McCarthyism, in an accusation against former President Barack Obama that was debunked by the FBI and the National Security Agency.

Is Donald Trump the new McCarthy? Or are the Democrats themselves guilty of McCarthyism by suggesting that there was collusion between the president and Russia in the last presidential election?

These vernacular uses of “McCarthyism,” to refer to unscrupulous accusations, are at odds with how historians understand McCarthyism, which is usually regarded as a phenomenon that goes well beyond the antics of one Republican senator. In her 1998 book Many are the Crimes: McCarthyism in America, Yeshiva University historian Ellen Schrecker argued that McCarthyism “was the most widespread and longest lasting wave of political repression in American history. In order to eliminate the alleged threat of domestic Communism, a broad coalition of politicians, bureaucrats, and other anticommunist activists hounded an entire generation of radicals and their associates, destroying lives, careers, and all the institutions that offered a left-wing alternative to mainstream culture.”

McCarthy, whose political dominance spanned four brief years from 1950 to 1954, was the crest of a very large wave—one that started surging before McCarthy gained public prominence, and which continued to flow after McCarthy disappeared. The danger of McCarthyism was that it was about much more than smear tactics. It was an ideology of political persecution broadly shared by those in power—not just in Congress, but mighty institutions like the FBI under Director J. Edgar Hoover. (The fact that Democrats are fully out of power in Washington is a convincing rebuttal of the idea that they’re the real McCarthyites.)

Hoover ran the FBI from the founding of the agency in 1935 until his death in 1972, and was a much more effective enemy of civil liberties than McCarthy, whose career of red-hunting ended in ignominy when he foolishly attacked a popular institution, the Army. Hoover not only prepared the groundwork for McCarthyism, but pushed it forward after McCarthy’s fall by continuing to spy on thousands of Americans, blackmailing politicians and political activists, and using the surveillance power of the state to punish radicals.

Given Hoover’s longevity and enormous influence, historians like Schrecker argue that what is popularly called McCarthyism is more accurately described as Hooverism: an ideological agenda in which state power is used to curtail civil liberties for a wide swath of the population.

Is Trump guilty of Hooverism? Not yet, but there are worrying signs that this is the road he’s on. Hoover believed in an intricate mythology about the powers of communism and why it was inimical to American life. Trumpism is far less ideological and more amorphous, a personality cult more than a coherent philosophy. Hoover hated communists because he thought they were trying to destroy America. Trump hates “treasonous” Democrats because he thinks—rightly, in some cases—that they’re trying to destroy his presidency.

As political scientist Corey Robin notes in Jacobin, there is far less ideological content to Trump’s feuds than in previous constitutional crises such as the Civil War, the New Deal battle over court packing, or the Watergate scandal. “What strikes me about the current crisis over Trump and the FBI, if that’s even what it is, is how far removed it is from the larger social questions that animated these previous crises,” Robin observes. “Obviously Trump and the GOP have a social base and are pursuing a social agenda, but the constitutional expression of the disagreement over the FBI and the Mueller inquiry bears no relationship to that social agenda.”

But the fact that Trump’s current quarrel is intellectually vacuous and personality-driven doesn’t mean that he can’t, in the future, deploy the same anger over weightier issues. Trump’s racism and anti-Muslim hatred could easily provide a basis for an reactionary politics as dangerous as anything Hoover or McCarthy were guilty of.

Trump’s current struggle is over pure power. He clearly wants to dominate the FBI and Department of Justice in a way that no president has attempted in post-Watergate America. If he does conquer these institutions, he would be in a position to revive Hooverism. He’d have both the power of the state and an ideology of anti-radicalism. Just as Hoover’s FBI spied on the Civil Rights movement and tried to manipulate its leaders, Trump’s FBI could wage an all out war against Black Lives Matter or the Council on American-Islamic Relations. Trump isn’t guilty of Hooverism, but that’s clearly the direction he’s heading in.