Roger Beale has written a series of five short commentaries on a growing political polarisation in USA politics.  In his third commentary (Causes) Beale identifies changes in the media contributing to this polarisation.  He notes:

The media – in all its forms

The growth of the internet, social media and broadcast media in all its forms has seen a new and worrying set of polarised reverberation chambers developing in American life.

The traditional mainstream media – broadcasting and print – considered it had an obligation to fact check news and used a “cross-fire” approach where contrasting opinions would be debated. Cable news and social media are more likely to identify an audience and present only views that audience finds comfortable and reassuring. Competition often requires these views to be presented in the starkest terms with other views held up to ridicule. The natural human tendency toward confirmation bias in seeking information leads to media consumers editing their own sources of news and opinion to ensure that they are not presented with information that would challenge their beliefs about the world.

The result of this has been plain to see in the internal emails discovered during the Dominion Voting Systems v Fox New Network. It was clear that Fox presenters and owners knew that Trump’s claim of a “stolen election” was untrue – but nevertheless to maintain viewer numbers they implicitly, and sometimes explicitly, supported the allegations of voting improprieties. Social media and on-line opinion sites took a similar approach. The result is that from 50-70 per cent of Republican voters still believe the 2020 election was stolen from them.

While these media changes might not have caused the difference in views held by Democrats and Republicans they have clearly contributed to a deepening of the affective polarisation between Republican and Democratic voters and states. Civil discussion and negotiation of issues across the dividing lines is becoming more difficult.

If you want to read these five commentaries, click on Political Polarisation in the United States.  Note that the Australian national public broadcaster, ABC, operates under a Charter and the PGPA Act, which together require honest & good faith reporting plus diversity of opinion.  This internal monitoring of its media coverage is even explicit in programs such as Media Watch; checking truth across a range of broadcast networks, including the ABC.  Next time the ABC presents something you don't agree with, it is only doing its job.  It is inherently a bulwark against the dreaded polarisation that can undermine a happy, tolerant and functional society.