Good morning, NBC News readers.

Here's one way to "unfriend" Mark Zuckerberg if he's your former college buddy: A Facebook co-founder has called for antitrust action to break up the tech giant.

Here's what else we're watching today.

'We are in a constitutional crisis,' top Democrat Nadler says

The House Judiciary Committee voted Wednesday to recommend that the House hold Attorney General William Barr in contempt of Congress for refusing to hand over special counsel Robert Mueller's unredacted report.

The move came hours after President Donald Trump asserted executive privilege to shield the full report and related materials from a House Judiciary Committee subpoena.

It represents a major escalation of the battle between congressional Democrats and the president.

"We are in a constitutional crisis," House Judiciary Committee Chairman Jerrold Nadler, D-N.Y., told reporters after the vote. "We are now in it."

While legal minds stew over how the fight for the special counsel's full report will ultimately play out, the Senate Intelligence Committee subpoenaed Donald Trump Jr. to answer questions in their Russia probe.

The committee, led by Republicans, is nearing completion of its investigation into Russian election interference.

Trump Jr. testified in 2017 that he was only "peripherally aware" of a Trump Tower Moscow deal. But Michael Cohen, the president’s former personal lawyer who is now behind bars for tax evasion, lying to Congress and campaign finance crimes, said he briefed the president's son on the topic at least 10 times.

North Korea has fired two missiles, South Korea says

North Korea fired two rounds of missiles Thursday, its second launch in a week, according the South Korean Defense Ministry.

Last week, North Korea launched what were described as several short-range projectiles.

Tensions have risen since Trump and dictator Kim Jong Un abruptly ended their nuclear summit earlier this year.

A co-founder of Facebook is calling for the government to break up the tech giant in an op-ed article published in The New York Times Thursday morning.

“The Facebook that exists today is not the Facebook that we founded in 2004,” Chris Hughes, who started Facebook with Mark Zuckerberg in their Harvard dorm, told NBC News.

“And the one that we have today I think is far too big. It's far too powerful. And most importantly, its CEO, Mark Zuckerberg, is not accountable,” Hughes said of his former business partner, whom he still called a “friend.”

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Plus

The decision to send additional U.S. forces into the Middle East was based in part on intelligence that an Iranian official had OK'd attacks on the American military, three U.S. officials say.

Robert F. Kennedy Jr.'s own family have called his anti-vaccine crusade "dangerous" and "wrong."

Common explained why he has opened up about being molested by a family friend as a child. “I hope being open about my childhood trauma can give others the strength to do the same," the rapper and actor said.

Mayor Pete Buttigieg is the only top Democratic candidate who is not offering staffers health care yet.

New York's Senate passed a bill that would make it easier for Congress to get Trump's state tax returns.

THINK about it

Trump's investments are earning him money in office. We need to know if it's clean, Rep. Jackie Speier, D-Calif., writes in an opinion piece.

Science + Tech = MACH

Uber and Lyft say they help ease traffic congestion. But a new study says otherwise.

Quote of the day

“I don't think that Mark Zuckerberg can fix Facebook. I think only government can — by making the market more competitive, by breaking it up, and by creating these privacy restrictions.”

— Chris Hughes, a co-founder of Facebook

One fun thing

What's in a name?

That seems to be the million dollar question everyone is asking after Prince Harry and the former Meghan Markle announced their baby boy will be called Archie Harrison Mountbatten-Windsor.

Is the name a nod to the famous American comic character or the cantankerous Archie Bunker? Who knows. But we break down what we do know about the royal moniker.

A doting great-grandmother: Baby Archie meets Queen Elizabeth II and Prince Philip while Meghan's mother, Doria Ragland, looks on. Chris Allerton / SussexRoyal via AP

Thanks for reading the Morning Rundown.

And thanks to several readers who wrote in to let me know that the link to the last video yesterday was broken. Apologies for that. Here is the correct link: You're defined by what you care about. Here's how to choose.

If you have any other comments — likes, dislikes — drop me an email at: petra@nbcuni.com

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Thanks, Petra