These media spaces of political congeniality contribute to the tendency of people to be influenced by peers and by those whom they perceive as knowledgeable and authoritative and who validate their beliefs.
Abetting this processes is the notion put forth by noted public opinion scholar Walter Lippmann, who developed the notion of pictures in the head, or a world view shaped not so much by facts but by a creative use of language.
"Whatever we believe to be a true picture, we treat as if it were the environment itself," Lippmann wrote in his seminal 1934 book "Public Opinion," in which he described the creation of what he identified as a "pseudo-environment."
"Let him cast a stone who never passed on as the real inside truth what he had heard someone say who knew no more than he did," Lippmann wrote.
This concept is what media theorists now call a constructed reality, an environment, similar to the flickering shadows on the wall that represented the real world for Plato's cave denizens, delivered through the print and electronic media from which most citizens gain their knowledge and understanding of their society.
Lippmann's observations remain valid in today's media world in which advertising and demagoguery create a pseudo-environment of false claims, loaded poll questions, out-of-context sound bites and misleading innuendo, all selectively ingested and regurgitated as though truthful and real.
That such propaganda is used in political campaigns is nothing new. But its volume and influence is louder and stronger than ever, thanks to a political and media environment that encourages it to thrive.
It probably is too much to hope that ad and public relations agencies follow their own written ethical codes and adhere to truth and responsibility. But in these times of heightened political and cultural partisanship, we can hope that more media outlets, particularly at the broadcast and cable level, adhere to their responsibility to deliver messages that honestly inform rather than hoodwink their audience.
And we can hope that, at the grassroots level, citizens move beyond selectivity and work to inform themselves and their neighbors to counter the misinformation that is rampant in the political environment.
Hallock is director of graduate studies for the School of Communication at Point Park University in Pittsburgh and author of "Reporters Who Made History: Great American Journalists on the Issues and Crises of the Late 20th Century."