Hours before South Bend Mayor Pete Buttigieg was to appear on the network on Sunday, Trump took to Twitter to criticize the network for “wasting airtime” with the presidential candidate.

“Hard to believe that @FoxNews is wasting airtime on Mayor Pete, as Chris Wallace likes to call him,” Trump wrote. “Fox is moving more and more to the losing (wrong) side in covering the Dems. They got dumped from the Democrats boring debates, and they just want in. They forgot the people who got them there.”

Hard to believe that @FoxNews is wasting airtime on Mayor Pete, as Chris Wallace likes to call him. Fox is moving more and more to the losing (wrong) side in covering the Dems. They got dumped from the Democrats boring debates, and they just want in. They forgot the people…..

— Donald J. Trump (@realDonaldTrump) May 19, 2019

Trump went on to belittle Fox News host Chris Wallace for having said of Buttigieg that “whether you like his opinions or not, that Mayor Pete has a lot of substance…fascinating biography.”

Trump wrote in a second tweet, “Gee, he never speaks well of me – I like Mike Wallace better…and Alfred E. Newman [sic] will never be President!”

Buttigieg is one of several candidates who have followed Sen. Bernie Sanders’ lead in their decision to appear on the network more frequently associated with the Trump administration and the Republican Party. Sanders paved the way in April, followed by Sen. Amy Klobuchar earlier this month. Gillibrand’s town hall is scheduled for early June, while a number of other candidates are already in discussion with Fox News or have expressed a willingness to appear. Sen. Elizabeth Warren, meanwhile, publicly rejected an invitation from Fox News last week, calling the network a “hate-for-profit racket.”

In March, Buttigieg advocated for such appearances, telling the hosts of The View that elections are “supposed to be about our whole country,” so he and his fellow Democrats “can’t just concentrate on those areas where people, for the most part, already agree with us.”

He further explained why he decided to do the town hall in an email to supporters on Saturday, noting that he “strongly condemn[s] the voices on Fox and in the media that uncritically amplify hate and the divisive sort of politics that gave rise to this presidency.”

At the same time, however, neglecting the Fox News audience amounts to surrendering “our ability to speak directly to millions of American voters” and thereby allowing conservatives to “tell our side of the story for us,” he said. As such, the appearance was a means to move “beyond the echo chamber of like-minded voices. ”

During the town hall Sunday, Wallace asked Buttigieg about Trump’s tweets, to which the mayor replied that he didn’t care. While he admitted that it’s “hard for anyone to look away” when Trump tweets, he acknowledged that “it is a very effective way to command the attention of the media. We need to make sure we are changing the channel.” But, he added, “it is the nature of grotesque things that you can’t look away.”

Buttigieg proceeded to receive a standing ovation from the New Hampshire crowd.

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