The recent decision by Congress to hold Steve Bannon, the former Trump adviser, in contempt, and the Justice Department’s willingness to take up the case, have had many liberals cheering.

“This is a big milestone,” Maya Wiley, the former New York mayoral candidate, wrote on Twitter. “#SteveBannon will face a DC jury! THAT is real & it matters!”

And it’s not just about Bannon, who is refusing to comply with a subpoena from the committee investigating the Capitol riot on Jan. 6. Several other former Trump officials have been subpoenaed, and are already defying the requests or appear likely to do so — setting up the likelihood that more contempt votes will come soon.

But Congress’s power to hold witnesses in contempt is a blunt tool, prone to abuse, and its history offers a cautionary lesson for modern legislators eager to deploy it.

On the morning of Jan. 24, 1946, a woman named Helen Reid Bryan entered a hearing room in the Longworth House Office Building on Capitol Hill. She was there to testify before the House Committee on Un-American Activities, known by its loose acronym HUAC, in her capacity as the executive secretary of a group called the Joint Anti-Fascist Refugee Committee, which provided money and resources to victims of the Spanish Civil War.

Strangely enough, HUAC had been founded in part to root out domestic fascism in the 1930s. But it had quickly been taken over by anti-New Deal, pro-segregation congressmen, who claimed that both the Roosevelt administration and the civil rights movement were being used as covers for Soviet infiltration into American society. For years, unsubstantiated rumors held that the refugee group was a front for the Communist Party, which is why Bryan had come before the committee.

Bryan arrived that morning with 200 supporters, who organized a protest outside. She did not, however, bring the organization’s records — just a statement, which she insisted on reading.

She had good reasons not to cooperate. Being a communist was legal (though she wasn’t one), and there were no allegations that her group was involved in subversive activities. More to the point, several members of HUAC were outspoken supporters of Francisco Franco, the fascist dictator in Spain, and Bryan worried that they might leak the records to Madrid, putting thousands of political refugees and their families at risk. But those weren’t sufficient reasons to defy a congressional committee. HUAC refused to let Bryan read her statement, and it voted unanimously to hold her in contempt.

The committee then called her boss, Edward Barsky, who appeared a month later and likewise refused to hand over the documents; so did the group’s entire board of directors, when they were called — including the novelist Howard Fast, who wrote about the experience in his memoir “Being Red.” All of them were held in contempt. None of them had been allowed to have their lawyers with them during their testimony.

The House met in April 1946 to vote on the contempt citation, and whether to send it to the Justice Department. While liberal and conservative members clashed over the committee’s mandate and the refugee group’s alleged foreign allegiance, the only issue at hand, said HUAC’s chairman, John Wood of Georgia, was whether private citizens could ignore the will of Congress.

“It is the purpose of our committee to determine, once and for all, whether an organization such as the Joint Anti-Fascist Refugee Committee has the authority to defy the Congress of the United States,” Wood declared.

Even many of HUAC’s skeptics found that logic hard to reject. “This committee is an established committee of this House,” said one of them, Clyde Doyle of California. “As long as it appears that the committee had acted within the law as we gave it to do, I shall feel compelled to back its lawful acts.”

The vote followed quickly, and decisively. Of the 430 House members present, 292 voted for contempt; 82 declined to vote and just 56 voted against. Bryan, Barsky and the bulk of the refugee group’s board went to jail, some for a year. For most of them, their lives were over. Barsky, a surgeon, lost his medical license. Bryan retreated to rural Vermont, unable to find an employer willing to hire her.

The greater consequence, though, was for the country. Having proven its power, HUAC next went after Hollywood, sending dozens of recalcitrant screenwriters to jail. Senators Kenneth Wherry and Lister Hill used similar threats to hound gay men serving in the federal government. Joseph McCarthy used those tactics to animate his four-year reign of terror.

Over the next decade, thousands of witnesses across all parts of society — schools, universities, unions, churches, newspapers — had to weigh their consciences versus their livelihoods in deciding whether to submit to what came to be known as the Red Scare. (Among those indicted was one of my predecessors on the Obituaries desk of The New York Times, Alden Whitman.)

If you’re a conservative, this story probably sounds familiar. You may already believe the Jan. 6 committee has overreached, and is using its subpoena power to fight a political war. If you’re a liberal, you might think that’s ridiculous — but it’s not hard to imagine the same thing happening to the left in the future, when a Republican Congress and a Justice Department led by a Republican president could go after, say, teachers who are accused of introducing critical race theory into their classrooms, or tech executives accused of working too closely with the Chinese government. House Republicans have already threatened to unleash a wave of subpoenas against the Biden administration if they regain the majority after next fall’s elections.

A full return to the darkest days of HUAC is unlikely. In 1957, the Supreme Court clipped some of the committee’s powers, ruling in Watkins v. United States that Congress could indeed hold someone in contempt for failing to answer a question “pertinent to the question under inquiry,” but that the question had to be clear and limited — that is, no fishing expeditions of the sort in which HUAC specialized.

But the court subsequently recognized, in Eastland v. United States Servicemen’s Fund (1975), that as long as Congress was pursuing a legitimate legislative goal with its subpoena, it was immune to judicial intervention, and it made clear that such goals could be broad and open-ended; no actual legislation needed to be at hand.

None of this is to say that Mr. Bannon should not be compelled to testify, or that the House is wrong in finding him in contempt. But liberals should be careful about celebrating the use of blunt government power to achieve what many Americans see as overtly political ends.