Last week, as the White House struggled to grapple with an accelerating impeachment probe and a bloodbath in Syria, President Donald Trump’s mind drifted to old, familiar territory: threatening frivolous and petty lawsuits.

With crises surrounding him, the president spent days privately grousing to those close to him about undercover video and audio, released by Project Veritas, purportedly showing a vast anti-Trump conspiracy orchestrated by CNN President Jeff Zucker. According to a source with direct knowledge of Trump’s grievance, the president repeatedly made clear that he wanted there to be consequences for CNN’s alleged malfeasance (though the released videos showed fairly mundane, if not outright boring, editorial meetings).

And consequences there were—at least in the form of a deeply meaningless letter.

Representing both the president and the 2020 Trump campaign, Gawker-killing celebrity lawyer Charles Harder sent a four-page document to Zucker and CNN General Counsel David Vigilante alleging the news channel was violating the law with its coverage. In the letter, Trump and Harder threatened to sue CNN for falsely advertising itself as a legitimate news outlet, in addition to seeking “substantial payment of damages” as part of some sort of resolution.

Reached for comment by phone on Friday, Harder simply hung up and wouldn’t answer questions about Trump’s role in crafting the letter. (The president has been known to enthusiastically suggest insults and jabs in his lawyers’ missives.) A Harder spokesman also declined to comment and said that the letter spoke for itself.

On Friday, CNN rejected the letter as “nothing more than a desperate PR stunt and doesn’t merit a response,” and numerous lawyer and legal experts laughed it off as amounting to little more than mere whining.

The delivery of the Trump attorney’s four-page document was a blip on the news cycle, but one that offered a glimpse into how the president has often responded over the decades when he feels besieged. In his game-show host years and real-estate days, he and his legal counsel would frequently lean on lawsuits and legal threats as an intimidation tactic—even if they knew there was no chance of it advancing in the courts. It’s a strategy that Trump hasn’t abandoned, even after he became leader of the free world. And with impeachment at the hands of House Democrats looming, one senior White House official said that the president’s impulse to sue, or say he’ll sue, “everybody who pisses him off” is only intensifying.

And it’s not just CNN. According to two people close to the president, Trump has also asked his lawyers and advisers about options for legal retaliation against other news outlets, including MSNBC and The Washington Post. Neither of these sources thought much of anything would come of Trump’s inquiries, and simply viewed it as part of the president’s habitual venting about his vast array of perceived enemies in politics and national media.

“The president’s first instinct on these types of things is very often: ‘Sue, sue, sue, then sue some more,’” one of these confidants said. “Doesn’t mean he gets what he wants.”

In recent weeks, Trump has also openly fantasized about suing one of his perennial Democratic foes, Rep. Adam Schiff (D-CA), the chairman of the House Intelligence Committee who leads the probe into the whistleblower complaint that kick-started congressional impeachment drive.

Trump’s personal attorneys Jay Sekulow and Rudy Giuliani (the latter of which remains at the center of the scandal and controversy fueling the impeachment inquiry) told The Daily Beast this month that they have been actively involved in discussions with the president regarding potential avenues for legal action against Schiff. Though none has been taken thus far, Sekulow said that “all options are on the table,” and that any legal maneuver or court challenge would focus on due-process issues. “We have five lawyers working on it, and I was up until 2 a.m. [one] night researching Supreme Court cases because I want to know the limits of congressional immunity,” Giuliani said early this month.

The president has even acknowledged that there may be zero legal standing for him to successfully sue the congressman. Nevertheless, Trump maintains that he just doesn’t care.

“Sue him anyway, even if we lose, the American public will understand,” the president said at a speech at this month’s Values Voter Summit in Washington, D.C.

“And sue Nancy Pelosi,” Trump added, for good measure.

To those who know the president, none of this is particularly surprising. Trump has long been a fan of frivolous legal action as a tool of retribution against celebrities, media personalities, and others. In 2013, Trump sued HBO’s Real Time host Bill Maher for $5 million after the comedian joked that he’d give away $5 million to charity if Trump could provide evidence that he wasn’t the “the spawn of his mother having sex with an orangutan.” (This was a satirical jab at the future president, who was then a key figure in the racist, anti-Obama birther movement that demanded that President Barack Obama prove he was in fact born in the United States.)

Predictably, nothing came of the suit.

In 2006, Trump very publicly threatened to sue comedian Rosie O’Donnell, then a View co-host and one of his arch-nemeses. “Probably I’ll sue her,” he proclaimed. “Because it would be fun. I’d like to take some money out of her fat-ass pockets” for some of her contemptuous comments about him and his business empire. He also said during this tirade that “Rosie’s a person that’s very lucky to have her girlfriend. And she better be careful or I’ll send one of my friends over to pick up her girlfriend [because] why would she stay with Rosie if she had another choice?”

This zeal for legal saber-rattling continued through his presidential campaign, and well into his time in office.

At one point early during the 2016 election campaign, Trump was watching his favorite cable channel, Fox News, and noticed a segment in which two hosts were having a heated argument about Trump, with one host saying things friendly to the future president and the other pushing back hard. Nothing slanderous or particularly explosive was said. Regardless, this didn’t stop Trump from picking up the phone shortly after the segment aired, and calling the Trump-friendly host to suggest to that person that they sue the other Fox News personality.

“I know a good lawyer [you can use],” Trump said, according to this person, who asked for the two hosts to remain anonymous as a condition of reporting this anecdote. The source recalled laughing and then politely declining the Republican presidential candidate’s offer.

—With additional reporting by Will Sommer