On CNN’s Reliable Sources, host Brian Stelter and former Daily Caller writer Mickey Kaus explained how Fox’s gigantic success has cost some conservatives their freedom of expression.

Kaus, you may recall, recently quit The Daily Caller after one of his columns was spiked for criticizing Fox - for not being conservative enough about immigration. Tucker Carlson, The Daily Caller’s editor-in-chief told Kaus that it’s a “non-negotiable” rule that The Daily Caller doesn’t “trash Fox.” Why? Because Carlson also works as a Fox News host.

On CNN, Stelter and Kaus discussed the bigger picture.

STELTER: When you say everyone is scared of Fox, you’re saying there are lots of writers, bloggers, up-and-coming stars in conservative media who don’t want to take on Fox, who don’t want to be critical of Fox because then they won’t get on the air. Is that right?

KAUS: Well, that’s right. I mean, Fox is basically the only means or the main means, the dominant means of upward mobility for a whole bunch of pundits and writers and wannabe pundits. Even if you don’t have a show on Fox, like Tucker does, you want to have a show on Fox. If you’re an author, if Fox promotes your book, your book’s going to be a success and the routes to success outside of TV, like, saying, being a midlist book author without any TV exposure – those are dried up. So TV is dominant and Fox is dominant on the right.

The root of the problem, these two agreed, is that Fox has a monopoly on the conservative market.

But I continue to ask, what is the excuse of all those professional “Democratic strategists” who go on Fox and fail to call out its tactics?

Watch the discussion below, from yesterday’s Reliable Sources.