The comments immediately drew criticism that the president was using his office to undermine First Amendment guarantees of free speech and free press. And, in fact, the networks themselves â and their news departments â do not hold federal licenses, though individual affiliates do.
âBroadcast licenses are a public trust,â said Tom Wheeler, who until January was chairman of the Federal Communications Commission, appointed by President Barack Obama. âTheyâre not a political toy, which is what heâs trying to do here.â
In suggesting that a broadcast networkâs license be targeted because of its coverage, Mr. Trump once again evoked the Watergate era when President Richard M. Nixon told advisers to make it difficult for The Washington Post to renew the F.C.C. license for a Florida television station it owned. A businessman with ties to Mr. Nixon filed paperwork to challenge The Postâs ownership of the station. The Justice Department under Mr. Nixon also filed antitrust charges against the three major television networks.
In Mr. Trumpâs case, it may just be an idle threat, the sort of bluster that he has regularly used to keep news organizations and other individuals and institutions he perceives to be rivals off balance. Just a day earlier, he went on Twitter to suggest using federal tax law to punish the National Football League as part of his campaign against players who kneel during the national anthem, only to have a spokeswoman later say he was only making a point.
But Mr. Wheeler said it could also be taken as instruction by his supporters who could act on his behalf. âThis sounds to me like another dog whistle for folks to file against the license renewals,â he said. âClearly it would be a bridge too far for the Trump F.C.C. to move on their own initiative. But if some conservative groups were to take this as their marching orders, it would be an interesting situation to see what the Trump F.C.C. did.â
Shortly after the tweet, Senator Edward J. Markey, a Democrat from Massachusetts, wrote a letter to Ajit Pai, the current F.C.C. chairman, who was designated by Mr. Trump to lead the commission, urging him to protect First Amendment rights. âI ask for your commitment to resist the presidentâs request and call on you to publicly refuse to challenge the license of any broadcaster because the president dislikes its coverage,â Mr. Markey wrote.
Mr. Pai did not immediately respond to a request for comment about the presidentâs tweet, nor did the White House.
The NBC story said that Mr. Trump raised the idea of increasing the nuclear arsenal during a July 20 meeting at the Pentagon. Shown briefing slides illustrating the reduction of nuclear weapons since the 1960s, the president said he wanted a major buildup instead.
National security officials, said to have been surprised by the presidentâs suggestion, explained that such a move would contravene decades of efforts to curb nuclear weapons and violate several treaties signed by the United States under Republican and Democratic presidents.
The network cited three officials who were in the room but did not identify them. As the meeting broke up, Mr. Tillerson was heard making his âmoronâ comment. Mr. Tillerson did not deny using the word when asked by reporters last week, but later sent out a spokeswoman to deny it on his behalf. In an interview posted on Tuesday, Mr. Trump said he considered that âfake newsâ â but also said that, if it were true, he could beat Mr. Tillerson in an I.Q. contest.
While its members are appointed by the president and confirmed by the Senate, the F.C.C. is a separate agency mandated to act independently from the White House. Mr. Trumpâs tweet suggested a potential misunderstanding of how television licenses work.
NBC, like ABC, CBS, Fox and CNN, are television networks that do not license spectrum. Therefore, there are no licenses held directly by networks that create programs, which are then pushed out to television stations to run over airwaves and into American homes.
But NBCâs parent company, Comcast, does own television stations that do license airwaves from the F.C.C., as do CBS and ABCâs parent company, Walt Disney. But the networks themselves, and NBC News in particular, do not license airwaves.
The presidentâs tweets stoked strong pushback from consumer groups that said the threat to NBC was clear.
âThis is not just a huge issue from a First Amendment standpoint, it is at best a weird way to go at it and nonetheless very problematic,â said Matt Wood, policy director at Free Press, an advocacy group on communications issues before the F.C.C. âThe message is clear, you donât have to work hard to see how those words are chilling.â
Alexandra Ellerbeck, the North America program coordinator for the Committee to Protect Journalists, said that authoritarian countries such as Russia, Azerbaijan, Saudi Arabia and Turkey license news outlets based on their coverage. âDonald Trumpâs assertion that NBCâs license could be challenged not only puts him in unfavorable company but emboldens other governments to embrace authoritarian tendencies,â she said.
Mr. Trumpâs threat was hardly the first time a president has sought to stifle the media. âTrump is following in one of our more sordid presidential traditions,â said John A. Farrell, author of âRichard Nixon: The Life.â
He noted that President John F. Kennedy pressured The New York Times to pull its reporter, David Halberstam, out of Vietnam because of his critical reporting on the war, and President Lyndon B. Johnson harassed Frank Stanton, the president of CBS, over the networkâs reporting from that war zone.
The Nixon White House âcarried the campaign against the press to considerable length,â Mr. Farrell said, including bugging reporters and infiltrating the press corps with dirty tricksters.
He cited a 1971 discussion, captured on Mr. Nixonâs secret tapes, in which Charles Colson tells the president that the threat of an antitrust suit âgives us one hell of a clubâ to hold over the networks. âOur game here is solely political,â Mr. Nixon replied. âAs far as screwing them is concerned, I am very glad to do it.â