But Trump's tweets generated alarm among First Amendment advocates, who said that they could have a calling effect on freedom of speech. "The FCC under my leadership will stand for the First Amendment", Pai said in an appearance at George Mason University.
Pai broke his silence on the issue Tuesday, saying that his agency "does not have the authority" to revoke licenses for an outlet's content.
The remarks were obvious but necessary.
Upset that NBC News reported that Trump sought a tenfold increase in the country's nuclear arsenal, the president tweeted that the network's broadcast license should be examined. In an October 11 tweetstorm, the president said the article was "pure fiction".
But Pai's statement didn't come soon enough-and wasn't clear enough-for some lawmakers. The FCC grants licenses to local stations, which then broadcast the networks.
Pai, a Republican, was appointed by Trump in January and confirmed by the Senate in a close vote that reflected some Democratic concern that he would hurt net neutrality rules that force service providers to treat all content the same. For one thing, NBC's main, national network isn't licensed by the USA government.
That proposal, like Trump's assertion that "licenses must be challenged and, if appropriate, revoked" in response to "partisan, distorted and fake" news coverage, is obviously anathema to the First Amendment. Pai said "traditionally that has not been within the FCC jurisdiction".
The FCC is the independent federal agency responsible for issuing licenses to individual broadcast stations on a staggered schedule for eight-year periods.
When reviewing licenses the FCC must determine if a renewal is in the public interest.
Critics quickly pointed out that there is no single license for NBC - or any other national television network for that matter.
Previously, telecom experts said that the FCC is unlikely to help Trump punish networks but that Pai may have been reluctant to say so publicly because Trump could demote him from the chairmanship, a Politico article said.
She also ripped her fellow commissioners and Pai for not speaking out in defense of the First Amendment in light of Trump's comments.