Irked by an NBC News story he claims is false, President Trump stated this morning that it may be time to “challenge” the network’s broadcast license. But what does that even mean — and would the Trump administration have the authority to yank a TV station’s access to the airwaves over a news story?

It all started when NBC News ran a report about the President claiming that he had at one point asked national security advisers for a massive increase in the nation’s nuclear arsenal.

Trump objected to the report, calling it “pure fiction” and denigrating it with his frequent epithet, “fake news.” Then, in a second tweet, he went a step farther, saying, “With all of the Fake News coming out of NBC and the Networks, at what point is it appropriate to challenge their License? Bad for country!”

He doubled down on his words in a press conference later in the day, adding, “It is disgusting the way the press can write whatever they want. People should look into it.”

This outburst left the internet with two major questions. One: what is a broadcast license, anyway? And two: can he do that?

What is a broadcast license?

When you boil it down, all of the data that travels to us wirelessly — from the oldest old-school AM radio to as-yet unavailable 5G mobile data — travels through radio waves, in a fairly narrow slice of the EM spectrum.

But as we learn in high school physics, when too many things try to use the same frequency in close proximity to each other, the signals interfere with each other, everything gets screwed up, and nothing works. So the Federal Communications Commission has long managed everything to do with who can use what stretches of spectrum.

That includes issuing licenses for all TV and radio broadcast stations.

A broadcast license grants a specific entity permission to carry its radio or TV station in a specific region, on a specific frequency (i.e., “102.5 FM” or “channel 12”).

In return for getting sole access to a certain slice of spectrum, the station operator agrees to operate in the “public interest, convenience and necessity.”

Who needs a broadcast license?

The FCC licenses individual TV and radio broadcast stations — but not cable, broadcast, or on-demand networks.

That’s a key difference. NBC is a network, not a channel.

Comcast, NBCUniversal’s parent company, does own several affiliate stations. Take, for example, New York City’s flagship NBC affiliate, WNBC (channel 4). That station, like any other, needs and has, a valid broadcast license. But its parent company, from which it gets network content, does not.

Do licenses mean the FCC regulates content?

For the most part, aside from obscene and profane content, no.

The FCC’s guide to broadcast licensing explicitly says that the free expression of a wide range of views is judged to be in the public interest — exactly what broadcasters are licensed to do.

“The First Amendment and the Communications Act bar the FCC from telling station licensees how to select material for news programs, or prohibiting the broadcast of an opinion on any subject,” the Commission explains.

There are two exceptions. The first are hoaxes: The FCC can intervene when a news broadcaster knowingly perpetuates false information that causes “substantial harm” that it should have foreseen.

The second is knowing perpetuation of false news, or “news distortion.” This is, as you might guess, something the Commission notes it often receives complaints about. However, it very rarely investigates such claims.

“The Commission generally will not intervene in such cases because it would be inconsistent with the First Amendment to replace the journalistic judgment of licensees with our own,” the FCC’s guide notes. If someone presents evidence that a broadcaster intentionally directed employees to falsify news reports, the FCC might investigate.

“However,” the Commission concludes, “absent such a compelling showing, the Commission will not intervene.”

And it’s been a long time since the Commission received such a compelling showing: Politico notes that the last time a U.S. broadcaster lost a license was in the 1970s, when a station’s management was convicted of bribery.

So, it’s an empty threat?

In the details, yes. NBC, as a network, doesn’t have a station license to begin with — and even if it did, the FCC’s own rules say it wouldn’t investigate or revoke it for doing broadcast journalism that one person, even the nation’s most powerful person, didn’t like.

However, observers note, just because the President’s threat is technically empty doesn’t mean it’s harmless.

Several outlets immediately drew a parallel to the Watergate era, when President Nixon tried to prevent the Washington Post — which of course broke the infamous Watergate story — from renewing the license of a station it owned in Florida.

Former FCC chair Tom Wheeler told the New York Times, “Broadcast licenses are a public trust. They’re not a political toy, which is what [Trump is] trying to do here.”

That sentiment was echoed by other past and present commissioners.

“This madcap threat, if pursued, would be blatant and unacceptable intervention in the decisions of an independent agency,” former FCC Commissioner Michael Copps, now an advisor to the advocacy group Common Cause, said in a statement. “The law does not countenance such interference … additionally, it’s not just NBC stations that will find this threat chilling, but also smaller independent stations around the country who might lack the resources to fight back.”

Current commissioner Jessica Rosenworcel, meanwhile, settled for Tweeting one very simple statement: “Not how it works.”

Want more consumer news? Visit our parent organization, Consumer Reports, for the latest on scams, recalls, and other consumer issues.