Story highlights Roger Ailes had a huge effect on American politics, Julian Zelizer writes

Donald Trump's presidency and the empire Ailes built are directly linked, Zelizer writes

Julian Zelizer, a history and public affairs professor at Princeton University and a CNN political analyst, is the author of "The Fierce Urgency of Now: Lyndon Johnson, Congress, and the Battle for the Great Society." He's co-host of the "Politics & Polls" podcast. The opinions expressed in this commentary are his own.

(CNN) On Thursday morning, Roger Ailes, the founder of Fox News, died. His passing is big news.

Ailes was one of the most influential members of the modern media. He created a television juggernaut that transformed the news business. Fox News introduced a style of politically driven news, leaning hard to the right, with in-your-face commentary and heated debate. It was a stunning success, introducing some of the most influential figures in journalism and offering a model that all other cable news stations paid attention to or emulated.

Julian Zelizer

This media mogul also had a huge impact on American politics. There is a direct connection between the presidency of Donald Trump and the empire that Ailes built. Through Fox News, Ailes promoted a new kind of conservatism. His television shows aimed to build a broad audience that was not limited to the country club set of high Republican politics. The hosts he featured, such as Bill O'Reilly and Sean Hannity, were meant to appeal to a blue-collar conservative audience that has been the heart and soul of the Trump coalition.

On Fox News, political discourse would not be restrained, and it could get very ugly. The hosts and the guests engaged in a fierce style of political debate that reset the terms of what was permissible in American politics. The station brought to television the kind of vitriol and demonization that had been characteristic of conservative talk radio in the 1970s. The shows featured commentary that demonized liberals as a danger to the nation rather than as people who held another point of view. False stories about issues like President Obama's birthplace made it onto a major network.

Social scientists have shown that Fox and other stations modeled after Ailes's empire had a huge effect on conservative voters. Conservatives were highly likely to believe what they heard on these networks, much more so than liberals, and this impacted their political decisions.

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