Donald Trump has gone so over the top with his “enemy of the people” ranting about the free press of the United States that there are those who may imagine he is merely making idle threats.

But the president and his authoritarian cabal upped the ante Wednesday when they lobbed a libel suit at The New York Times.

The lawsuit, which was filed by Trump’s campaign in New York State Supreme Court, alleges that what is frequently referred to as the nation’s “newspaper of record” defamed the campaign when it published a 2019 opinion piece by former editor Max Frankel under the headline “The Real Trump-Russia Quid Pro Quo.”

Frankel’s op-ed argued—as many sincerely believed at the time and many sincerely believe today—that “there was no need for detailed electoral collusion between the Trump campaign and Vladimir Putin’s oligarchy because they had an overarching deal: the quid of help in the campaign against Hillary Clinton for the quo of a new pro-Russian foreign policy, starting with relief from the Obama administration’s burdensome economic sanctions. The Trumpites knew about the quid and held out the prospect of the quo.”

As the president seeks a new term, however, the Trump camp proposes “to hold the news organization accountable for intentionally publishing false statements.”

The response from the Times has been thoughtfully dismissive. “The Trump Campaign has turned to the courts to try to punish an opinion writer for having an opinion they find unacceptable,” the paper’s statement declared. “Fortunately,” it added, “the law protects the right of Americans to express their judgments and conclusions, especially about events of public importance. We look forward to vindicating that right in this case.”

This is true. The Constitution established, and the courts have confirmed, that writers and publishers have a right to criticize public figures—and there is no more public a figure than the president of the United States. As the Authors Guild, the nation’s oldest and largest professional organization for writers, has noted, “The ability to criticize the government and its leaders lies at the essence of the First Amendment’s protection of free speech; and threats of libel lawsuits are one of the de facto primary means of curtailing free speech in this country today.”

But Trump has a long history of threatening to take legal action against his critics. In 2018, for instance, the president’s lawyers tried to block publication of Michael Wolff’s tell-all book Fire and Fury: Inside the Trump White House. As the Authors Guild explained at the time, “It is one thing for a private citizen to use libel laws to quash speech. It is unheard of for a sitting President to do so.”

Now, with the libel suit against the Times, the Freedom of the Press Foundation warns that Trump is “escalating his battle with the press.” That’s the proper assessment.

This litigious president has frequently championed the dangerous doctrine that existing protections against abusive libel actions—which he refers to as “a sham and a disgrace”—should be weakened in order to allow officials like him to sue writers and publishers. During the 2016 campaign, he threatened to “open up” America’s libel laws. In 2018, he pushed Congress ”to take a strong look” at altering protections that serve as an essential bulwark of freedom of the press.

It will be hard to weaken protections that have been so broadly understood and accepted. But if Trump were to be reelected in 2020, and if he were to continue to pack the courts with zombie jurists who are more loyal to a president’s authoritarian instincts than to the Constitution or the rule of law, the threat level would rise.

So it is vital that the president’s rivals push back during this year’s campaign with a steady freedom-of-the-press vision, as Vermont Senator Bernie Sanders has in issuing a statement that declares: “Let’s be clear: we have a president who believes he is above the law and can do and say whatever he wants without consequences. Donald Trump has ignored the Constitution, disregarded the will of Congress, and attacked the judiciary. Trump has called the press the ‘enemy of the people,’ and now—taking a page from his dictator friends around the world—is trying to dismantle the right to a free press in the First Amendment by suing the New York Times for publishing an opinion column about his dangerous relationship with Russia.”

“Enough,” concluded Sanders. “Donald Trump is the most dangerous president in modern history, and this November we will defeat him, restore the rule of law, and protect our constitutional rights.”