President Trump spoke about the media while at the Celebrate Freedom Concert in Washington D.C. on July 1. (The Washington Post)

President Trump loves to bash the “failing” New York Times. He plunged his rhetorical war on Mika Brzezinski and Joe Scarborough to a sexist new low last week.

But Trump's favorite foil is CNN, which, according to a running tally maintained by the Upshot, the president has insulted more than 100 times — on Twitter alone.

The most recent — and indisputably most over-the-top — dis was Sunday's tweet featuring the hashtags #FraudNewsCNN and #FNN under a video clip of Trump's performance at WrestleMania 23 in 2007. At that event, Trump tackled and pummeled WWE chief executive Vince McMahon; in the clip Trump posted online, a CNN logo was superimposed over McMahon's head.

CNN's coverage of the president is often critical, to be sure, but other news outlets are more strident. In fact, CNN employed a stable of pro-Trump commentators during the campaign, some of whom it retained after the election, and was often criticized by Trump detractors for devoting generous amounts of airtime to his rallies.

So, why does CNN hold such a special place in Trump's media-hating heart? Here are a few big reasons:

It's television

Sure, Trump reads newspapers and pays attention to Breitbart News, but television is far and away his preferred medium. The Washington Post's Ashley Parker and Robert Costa explained why in an April story about the president's obsession with cable news:

The president’s fascination with television is born of personal experience. Trump, long a fixture in the New York tabloids, did not become a household presence until 2004, when he began hosting NBC’s hit reality TV show “The Apprentice.” He relished the attention, boasting about and fretting over his ratings, much as he now handles political polls.

Trump recognizes that TV had the power to make him a star in a way that the written word could not; he seems to think that TV also has a unique power to destroy his political ambitions.

Trump would not waste his time on CNN if he did not perceive the network as a threat, and CNN seems more threatening because it is television.

CNN positions itself in the middle

If Trump fixates on television and hates criticism, then why isn't MSNBC his No. 1 target?

Probably because criticism from MSNBC is so predictable.

Thin-skinned as he is, Trump generally ignores liberal voices who reflexively oppose Republicans. When is the last time you heard him gripe about the New Yorker or HuffPost? Or Rachel Maddow and Lawrence O'Donnell?

Trump knows his supporters don't pay attention to these voices, anyway. In his world, they just don't matter very much.

CNN, however, positions itself between MSNBC and Fox News. As a result, Trump seems to perceive CNN as wielding at least some influence over his base.

And, although he probably wrote off positive coverage from MSNBC as impossible on the day he launched his campaign, Trump probably thought he could win over CNN. His inability to do so must be frustrating.

Jeff Zucker

One reason Trump may have expected friendlier coverage from CNN is Jeff Zucker, the network president, who led NBC Universal during Trump's run on “The Apprentice.”

Trump expects his personal relationships with media figures to produce positive coverage. That's how it works with David Pecker at the National Enquirer, and Trump seems not to understand why things do not work the same way with Brzezinski and Scarborough or with Zucker. Recall that Trump even boycotted Fox News briefly during the Republican primary because he thought the network owned by his pal Rupert Murdoch was not being kind enough to him.

The president values loyalty at a premium. The way he sees it, Zucker has been tremendously disloyal, which makes Trump's anger at CNN burn even hotter.