Michael Avenatti isn’t sure that he’ll ever go on Tucker Carlson’s Fox News show again — but he thinks every Democrat who’s serious about running in 2020 should if they want to prove they have what it takes to go up against President Donald Trump.

“Sometimes you’ve got to go into the belly of the beast. You can’t call yourself a fighter and then turn out to be a paper tiger,” Avenatti said in a Friday interview, dismissing the Democrats who have written off appearances with Carlson, and Fox News more broadly, given the channel’s often clearly pro-Trump bent.

Carlson said explicitly to Avenatti during Thursday night’s show that he wouldn’t insult the lawyer, best known for representing Stormy Daniels but now traveling the country talking up a White House run of his own. But over the course of the appearance, Fox News showed five different chryons that used the phrase “creepy porn lawyer” (the phrase apparently seemed so familiar that in one of them, the producers just went with the initials CPL).