But only 19 days later, as the election approached, Chaffetz took a different tack—saying while he would not endorse Trump, he would vote for him. And after Trump won the election, Chaffetz, the chair of the key House oversight committee, became one of Trump’s most enthusiastic cheerleaders, making clear that he would not look at Trump’s transgressions and violations of the Constitution’s Emoluments clauses, but still wanted to keep the focus on Hillary Clinton’s emails.

A similar phenomenon hit Speaker of the House Paul Ryan, who in a conference call with his members after the tape said, “His comments are not anywhere in keeping with our party’s principles and values. There are basically two things that I want to make really clear, as for myself as your speaker. I am not going to defend Donald Trump—not now, not in the future. As you probably heard, I disinvited him from my first congressional district GOP event this weekend—a thing I do every year. And I’m not going to be campaigning with him over the next 30 days.”

Trump campaign advisor Steve Bannon subsequently called Ryan “the enemy,” and the speaker suffered repeated barbs tossed his way by Trump. But since the election, Ryan has gone through multiple contortions to explain away Trump’s misbehavior and avoid direct criticism of the president, even as he has at times criticized indirectly Trump’s comments, behavior, and tweets. And the same holds for all but a handful of Republicans in the House and Senate, doing everything they can to avoid hitting the president and providing little in the way of checks and balances on things like Russian interference in the election and Trump’s kleptocratic behavior.

There are two reasons for this. One is that Republicans in Congress fear the backlash from taking on the president. Trump has shown that he will not hesitate to hit back directly and personally at lawmakers who do so—and that in turn will resonate with the president’s ardent base. That base may only be 35 percent or so of the electorate, but it is 75 percent of Republican identifiers, concentrated among the most active primary and caucus voters—and these voters are also the base of support for Republican lawmakers.

But the fear is not just about incurring the wrath of activist voters. Taking on Trump also means taking on his media acolytes—Sean Hannity, Tucker Carlson, Fox & Friends, Breitbart, Rush Limbaugh, Alex Jones, Laura Ingraham, Mark Levin, and a bevy of bloggers who have their own independent power with conservatives. When Limbaugh, Levin, and Ingraham decided to target then-Majority Whip Eric Cantor, they precipitated his stunning primary defeat to Tea Party insurgent Dave Brat, a lesson that has not been lost on other Republican lawmakers, especially the leaders. And there is the all-important money factor, that billionaire Trump supporters like the Mercers might help finance primary challengers to the apostates.