I am listening to "The Republic of Spin" by David Greenberg, Rutgers professor of history and journalism. The book is the history of presidential spin, attempts to slant the news by the White House and its political allies. The series begins with McKinley and Teddy Roosevelt, who became president when McKinley was assassinated. McKinley (president of the US from 1897 to 1901) and Roosevelt became focused on the transmission of information and opinion from newspapers to the public. I suspect that previous presidents were aware of the role of newspapers, the media of the time, too, but it may have been the size and wide distribution of the population that brought about an increased interest in news management.
As radio and later, television, became available and greater portions of the public, the same sorts of issues arose: is the president and his staff purposely slanting the news? Does his grip on newspapers or on radio stations or on television broadcasts give him too much power to control the public's opinion? The advent of radio and the high skill that FDR had in speaking to the public in "fireside chats" seemed to give him too much access to the voters. His opposition feared he would be too firmly entrenched. Television took a some time to supplant radio but it seemed, similarly, that warm, handsome JFK would be such a heartthrob, so good-looking, so manly that voters would clasp him to their hearts forever.
When Lynn was in graduate school, she had many assignments dealing with the postmodernist approach. Basically, it was a time of hypersensitivity to the fact that everything I say or write comes from me, and I may well be a slanted source of information. Hyperbole and exaggeration and blowhard assertion ("I am the greatest blog writer you have ever encountered") are not the potent, hypnotizing strategies they were feared to be. People today are more armored against ridiculous claims but that doesn't stop the claimers. Such claims do help them look silly.