Signage at the 20th Century Fox Studios in Los Angeles. (Bloomberg)
Daniel W. Drezner is a professor of international politics at the Fletcher School of Law and Diplomacy at Tufts University and a regular contributor to PostEverything.

Political scientists used to debate the existence of a “CNN effect” to explain foreign interventions. The logic was that if CNN aired a humanitarian catastrophe, enough Americans would be viscerally affected by the haunting images to call for something to be done.

The evidence for any CNN effect in the post-Cold War era remains a debatable proposition. Last year, however, when President Trump decided to launch Tomahawks at Syria in response to a chemical weapons attack, I joked to NPR: “We’d have to rename it. It’s the Fox News effect more than the CNN effect now.”

The thing is, this no longer a joke.

The past month has made it quite clear that Fox News plays an outsized role in Donald Trump’s information diet. We know from Axios’s Jonathan Swan that the presidential schedule has evolved over the past year to enable Trump to watch more television:

President Trump is starting his official day much later than he did in the early days of his presidency, often around 11am, and holding far fewer meetings, according to copies of his private schedule shown to Axios. This is largely to meet Trump’s demands for more “Executive Time,” which almost always means TV and Twitter time alone in the residence, officials tell us….

Trump’s schedule wasn’t always like this. In the earliest days of the Trump administration it began earlier and ended later. Trump would have breakfast meetings (e.g. hosting business leaders in the Roosevelt Room). He didn’t like the longer official schedule and pushed for later starts. The morning intelligence briefing ended up settling around 10:30 am.

Compared to last year, the president has built in more unstructured time to watch television in 2018. And Trump, like most Republicans, watches and trusts Fox News far more than any other outlet.

Further evidence comes from Trump’s use of Twitter. Matthew Gertz of Media Matters has closely examined Trump’s tweets and compared them to Fox News Channel content, and reaches a startling conclusion:

Here’s what is shocking: After comparing the president’s tweets with Fox’s coverage every day since October, I can tell you that the Fox-Trump feedback loop is happening far more often than you think. There is no strategy to Trump’s Twitter feed; he is not trying to distract the media. He is being distracted. He darts with quark-like speed from topic to topic in his tweets because that’s how cable news works.

Here’s what’s also shocking: A man with unparalleled access to the world’s most powerful information-gathering machine, with an intelligence budget estimated at $73 billion last year, prefers to rely on conservative cable news hosts to understand current events.

It is not hard to point to specific examples of Trump reacting to Fox News coverage.

As my Washington Post colleague Philip Bump noted Wednesday, Trump parrots Fox News talking points regardless of whether they are grounded in reality. Trump’s addiction to Fox News is so strong that last week it threatened to scuttle the House reauthorization of Section 702 of the FISA Amendments Act. Trump issued an early morning tweet in response to Judge Andrew Napolitano’s criticism on a “Fox and Friends” segment. Only direct intervention from the chief of staff, national security adviser, director of national intelligence, CIA director, and House Speaker Paul Ryan convinced Trump to post a follow-up tweet clarifying his position.

Just as Trump has paid more attention to Fox News, the channel has lavished more favorable attention on the president. As Vanity Fair’s Gabriel Sherman observes, the Rupert Murdoch-owned network has hewed closer to the Trump line over the past year:

Fox producers saw ratings drop whenever something negative about Trump was said on air. Since then, Fox has shed prominent Trump critics like Megyn Kelly, George Will, and Rich Lowry, while bulking up on pro-Trump voices such as Seb Gorka, Laura Ingraham, and Mark Levin. “The network has become a safe space for Trump fans,” said an executive….

Now, some prominent voices at Fox openly seem to be aiding the Trump agenda. In recent months, hosts such Sean Hannity, Jesse Watters, and Jeanine Pirro have promoted wild conspiracy theories about Trump being the victim of an F.B.I.-led coup. In December, The New York Times reported that Pirro had a one-hour Oval Office meeting with Trump where she denounced Special Prosecutor Robert Mueller and Attorney General Jeff Sessions.

The network has clearly become a safe space for the president himself, and based on his tweets, he is paying attention to the morning and evening commentators, not the more professional hard news programs that run during the day.

This is a problem. Vox’s Matthew Yglesias warned about the oddity of the commander in chief relying more and more on a news channel devoted to making him look good:

Trump-era Fox has frequently been compared by its critics to a state broadcasting network in an authoritarian regime. But the Soviet Union’s top leaders were not relying on their own propaganda outlets for information about the world. For the president to govern effectively, actual problems need to be brought to his attention. But in the propaganda bubble that Trump prefers to inhabit, there is no endless darkness in Puerto Rico or falling life expectancy amid a growing opioid crisis.

To be fair, not even “Fox and Friends” always toes the Trump line. Still, the pattern is clear: Fox News tends to stress administration accomplishments, minimize setbacks to the Trump agenda and hype the threats from the usual suspects overseas.

All of this makes Trump feel better, and allows him to bluster against Kim Jong Un or the Iranian mullahs. But there are clear blind spots in the Fox News bubble, and those can become Trump’s blind spots. The president might believe that he would profit from a government shutdown because Fox News will try to place the blame on Democrats. Fox News is less likely to cover instances of allies helping the United States overseas, thus reaffirming the president’s convictions that America’s partners do not pull their fair share. Fox is likely to give short shrift to the Freedom House report on “an accelerating decline in American political rights and civil liberties.” If things start going south in Afghanistan, I doubt Fox News will be on the forefront of coverage.

Most important, Fox News will be far less likely to cover Trump scandals. That means in turn, that Trump may be slow in responding to the scandals that everyone else is discussing. Indeed, we can see this with the Axios story about “Executive Time”. Trump is clearly sensitive to the idea that he watches too much television. But since to my knowledge Fox News has not really covered Swan’s story, Trump has not pushed back on it.

Just as the CNN effect is subject to debate, it is worth pointing out the limits of any Fox News effect. The president’s actual advisers were able to get him to reverse his position on the Section 702 authorization. If anything really important crops up, Trump will hear about it eventually.

Still, if any president is going to be vulnerable to a Fox News effect, it is a president who cannot separate good arguments from bad ones.

In theory, Trump’s Fake News Awards are supposed to happen tonight. Fox News commentators seem super-excited about them:

The Fox News Channel is feeling petty smug about the whole thing. It would be a cruel irony if their cheerleading helped sabotage the president they back to the hilt.