WikiLeaks founder Julian Assange in London in 2016 on the balcony of the Ecuadorian embassy, where he has been granted asylum. (Ben Stansall/AFP/Getty Images)

Lady Gaga — all in black and wearing a witch’s hat — is interviewing Julian Assange in the Ecuadoran Embassy in London, where he’s been holed up for years.

As the pop star, in a bizarre scene from a new documentary, quizzes the WikiLeaks founder about everything from his legal problems to his favorite food, Assange interrupts: “Let’s not pretend for a moment I’m a normal person.”

Indeed, in Laura Poitras’s film about Assange, “Risk,” he comes across as neither normal nor particularly sympathetic.

Consider: He has been accused of rape in Sweden (he says he was entrapped and had to seek asylum from extradition); he has published leaked information that has intruded into private lives; and he may have helped Russian agents try to get Donald Trump elected president.

But everyone who cares about the free press in America needs to understand something else, too.

Prosecuting Assange under the Espionage Act for publishing leaked information — which Attorney General Jeff Sessions calls “a priority” — is dangerous. It could turn out to be a major move toward what President Trump has long been threatening to do: punish the independent media in America.

“I’m going to open up our libel laws so when they write purposely negative and horrible and false articles, we can sue them and win lots of money,” Trump said during the presidential campaign.

That’s not so easy to do. But punishing Assange may begin to accomplish similar goals. And because Assange’s methods are questionable, such prosecution may not seem like much of a threat.

“When governments are trying to restrict press rights of any kind, the inclination is not to go after the most popular kid in the room — it’s to go after the least popular,” Trevor Timm, executive director of the Freedom of the Press Foundation, told me.

What WikiLeaks has consistently done, Timm said, “is publish information that is true and that the government considers secret. That’s the same thing that the New York Times or The Washington Post does all the time.” (Sessions’s threatened prosecution reportedly would not focus on the Russian hacks of Democratic officials’ emails, which during the campaign prompted Trump to proclaim: “I love WikiLeaks!”)

FBI Director James B. Comey seemed to join Sessions in laying the groundwork when he testified before the Senate Judiciary Committee last week, describing WikiLeaks’s publication of classified documents as “intelligence porn.”

Asked to lay out the difference between that and what he considers legitimate journalism that’s protected by the First Amendment, Comey said: “It crosses a line when it moves from being about trying to educate a public [to] just pushing out information about sources and methods without regard to interests.”

That raises troubling questions about what happens when the government decides that some news isn’t sufficiently educational.

Comey made another distinction: Legitimate journalists who obtain sensitive leaked information usually get in touch with government officials to hear their objections. But WikiLeaks doesn’t, he complained. (Assange quickly responded on Twitter, citing one specific example in which he did.)

Think about that. What if contacting the government becomes a legal prerequisite for publication? It would take away some of the media’s independence. It might even lead to a next level in which news organizations must get government approval before publishing. Now we’re into authoritarian territory.

To be sure, many in the government — and citizens, too — argue that journalists shouldn’t get to decide what classified information the public sees. Publishing may harm national security; classified information is secret for a reason.

Decades ago, one journalist made a powerful counterargument. As the New York Times was fighting to publish the Pentagon Papers, the secret history of the Vietnam War, Washington bureau chief Max Frankel wrote an affidavit describing how government officials “routinely misuse and abuse” classification.

They do it “to hide mistakes of judgment, to protect reputations of individuals, to cover up the loss and waste of funds,” Frankel wrote. “Almost everything in government is kept secret for a time and, in the foreign policy field, classified as ‘secret’ and ‘sensitive’ beyond any rule of law or reason.”

Given that, it falls to the news media to ferret out information about government activities that citizens ought to know. For example, in 2005, Dana Priest of The Washington Post brought to light the CIA’s “black sites,” where terrorism suspects were secretly imprisoned and tortured; her investigation won a Pulitzer Prize.

Priest sees the hazards of going after Assange.

“Assange is obnoxious, and probably reckless sometimes,” she told me, “but it would set such a bad precedent to prosecute a publisher” of classified information.

The legal lines between WikiLeaks and traditional news organizations aren’t clear.

“If Assange becomes the first successful prosecution of a third party under the Espionage Act, then that gives the government a whole lot of leverage it might previously have not thought it possessed to be much more aggressive in investigating the media’s role in national security leaks,” Stephen I. Vladeck, a University of Texas law professor, said recently.

Jail Assange and we could be on the road to government control of the news media.

Can we trust President Trump not to rush down that road as fast as he can? Remember: He called to congratulate Turkish President Recep Tayyip Erdogan, whose accumulation of authoritarian powers includes jailing nearly 150 journalists. And recall that Trump seldom stops ranting about America’s “out-of-control” media.

Clearly, this president wants to get the press under control. And whatever you think about Julian Assange, that way lies tyranny.

An earlier version of this column incorrectly described the nature of rape allegations against Julian Assange. Swedish authorities have issued an arrest warrant for Assange, but there have been no formal charges. The column has been updated.

For more by Margaret Sullivan visit wapo.st/sullivan