So with Trump grumbling about FCC licensing some people are digging up Nixon-era grumbling on the same topic, that’s a start.

But the REAL way that FCC licensing was leveraged was with regards to newspaper companies getting into first radio and then TV. Newspaper barons and editors were always powerful players in the political world, often upstream of senators and even bosses, but negotiations with over the number of stations one company could own, or own in one market gave government the whip hand - newspapers might have high profit margins, especially as the number per city fell, but maximum volume and no room for expansion, while broadcasting was the future.

Liscensing of individual stations would be premised on its being found to serve the public interest, which the bright young things running things since FDR - the open-minded, college-educated, even queer-positive types of their day – might understand as eschewing dangerous politics in favor of What All Right-Thinking People Knew

Weighing heavily on their mind that when Europe just tried to mix democracy with a vibrant and competitive mass media it polarized society into extremisms that turned and fell upon each other in the greatest apocalypse the world had ever seen, so

One Sulzbergerian even-handed newspaper per city and a handful of poorly-differentiated TV networks all pushing the same Postwar Consensus, radio operating under the Fairness Doctrine, a lot of the cultural blandness people associate in retrospect with the ‘50s, that was brought about by effort

The Mayflower Doctrine, I’d never even heard of that before Wikipedia right now. FDR’s regulations on broadcast editorializing, so that they would present responsible takes on public issues, rather than any old (fake news?) ones their (maybe anti-New Deal) owners or advertisers favored.

It was a Postwar Liberal Consensus, that’s why conservatives strained against it, especially after the ‘60s when coalitions and issues had shifted, ESPECIALLY under Reagan, whose victories seemed to affirm them as the proper agents of public authority. That’s why Reagan ended the Fairness Doctrine, that’s why so much conservative/Republican infrastructure is alternative channels for mass communication and coordination – AM talk, religious broadcasting, large-scale direct mail, national networks of activist cells piggy-backing off church or housewives’ affinity groups.