Facebook CEO Mark Zuckerberg makes rounds of meeting in Russell Building where he discussed technology regulations and social media issues with senators on Thursday, September 19, 2019. He was making his way from a meeting with Sen. Mike Lee, R-Utah, to one with Sen. Josh Hawley, R-Mo. (Photo By Tom Williams/CQ-Roll Call, Inc via Getty Images)

Last week, Facebook CEO Mark Zuckerberg made a trip to Washington, D.C., to hold court with some of his most vocal critics on Capitol Hill.

Sen. Mark Warner, D-Va., organized a dinner with about half a dozen U.S. senators on Sept. 24, where both sides talked about where they stand on privacy and antitrust regulation. Sen. Richard Blumenthal, D-Conn., who also attended the dinner, told NBC News last week there was a "positive" discussion on Facebook's various privacy issues. Zuckerberg also met with Republican Sens. Josh Hawley of Missouri and John Cornyn of Texas.

Based on the messaging from Facebook and lawmakers, the discussions were congenial and productive. As Facebook and other tech companies such as Google and Amazon face antitrust probes by the Federal Trade Commission and the Department of Justice, Zuckerberg decided to travel across the country and engage with lawmakers to prove he's serious about cleaning up his company.

But on Tuesday, the world got a hint of Zuckerberg's real thinking after The Verge published two hours of leaked audio from a July meeting between the CEO and employees.

According to the leaked recording, Zuckerberg blasted Democratic presidential candidate Sen. Elizabeth Warren's plan to break up Facebook and other Big Tech companies. He called it an "existential" threat and something the company would fight if Warren, of Massachusetts, wins the presidency.

"I mean, if she gets elected president, then I would bet that we will have a legal challenge, and I would bet that we will win the legal challenge," Zuckerberg said of Warren in the July meeting, according to the leaked audio recording.

"And does that still suck for us? Yeah. I mean, I don't want to have a major lawsuit against our own government. ... it's like, we care about our country and want to work with our government and do good things. But look, at the end of the day, if someone's going to try to threaten something that existential, you go to the mat and you fight."

Zuckerberg also repeated the company's line that breaking up Facebook would hurt its ability to fight abuse and election meddling, adding that more has been spent on Facebook safety than all of Twitter's revenue.

Facebook did not respond to requests for comment on the leak. But Zuckerberg did share The Verge's transcript on his Facebook page, calling it an "unfiltered" look at his thoughts.

The leaked audio shows that Facebook's apparent openness toward regulation is theater. In public, Zuckerberg calls for regulation in Washington Post op-eds and engages in well-publicized meet-and-greets with senators. But behind closed doors, proposals from lawmakers such as Warren are "existential" threats that will lead to lawsuits and political fights.

Any Facebook cynic probably guessed this was the case: Zuckerberg is willing to work with the government only to the extent that Facebook can have some influence over the final result. It's about fighting for weak regulation, not about full cooperation.

But now we have the receipts. From now on, anything he says publicly or to lawmakers on the matter will just come off as political theater.