Roger Ailes, president of Fox TV, in the Fox TV control room. (Helayne Seidman/for The Washington Post)

This past week, Fox News honcho Roger Ailes learned the same lesson that the entire Republican field has been made to understand in this campaign: When you fight with Donald Trump, you lose.

Trump began the week by flirting, yet again, with the idea of not participating in Thursday’s debate on Fox, citing past “unfair” treatment from moderator Megyn Kelly. He even put up a Twitter poll asking his millions of followers what they thought he should do.

Then Fox did this: “We learned from a secret back channel that the Ayatollah and Putin both intend to treat Donald Trump unfairly when they meet with him if he becomes president,” said a news release, apparently written by Ailes. “A nefarious source tells us that Trump has his own secret plan to replace the Cabinet with his Twitter followers to see if he should even go to those meetings.”

Trump does not like to be mocked. He abruptly canceled his plans to attend the debate and instead scheduled a counter-rally, billed as a fundraiser for veterans, just a few miles from the Iowa debate hall. In typical Trumpian fashion, he dismissed the debates without him as “low-rated afterthoughts.”

The Trump-less debate proved the Donald right. It was, in the main, a vanilla affair with few memorable moments as the seven candidates onstage played it safe; the Iowa caucuses loom. The ratings, too, were decidedly un-Trumpian. While more than 24 million people watched the first GOP presidential debate on Fox, just 12.5 million watched this one.

Donald Trump didn't attend the Fox News GOP debate on Jan. 28, but that didn't stop nearly everyone from talking about him. (Jenny Starrs/The Washington Post)

Roger Ailes, for becoming the latest victim of the Trump juggernaut, you had the worst week in Washington. Congrats, or something.

Each week, Chris Cillizza awards the worst week in Washington to an inhabitant of Planet Beltway who stands out for all the wrong reasons. You can check out previous winners or email Cillizza with candidates. You can also read more from Outlook and follow our updates on Facebook and Twitter.

Republican Donald Trump skipped the debate where Fox News anchor Megyn Kelly co-moderated. Here's a look back at the clash that started with an earlier debate in August 2015. (Sarah Parnass/The Washington Post)