Iowa’s other Republican senator, Joni Ernst, “ducked into an elevator as she was being asked” about what King had tweeted, saying that she wasn’t up to speed on the situation and “shrugging her shoulders as the elevator doors closed,” Stolberg wrote.

Shrugging their shoulders: That sums it up. Republicans shrugged last autumn when King endorsed a white nationalist running for mayor of Toronto and also when he did an interview with a far-right Austrian website and said that America must “defend Western civilization” against immigrants or be “subjugated by the people who are the enemies of faith.”

One of the few senior Republican officials who emphatically rebuked this behavior was Steve Stivers of Ohio, then the chairman of the National Republican Congressional Committee . “It could have been a pile-on moment when Republican leaders finally came out and denounced the guy,” Jonathan Weisman, who edits The Times’s congressional coverage, recalled. “But that didn’t happen. We were weeks before the election.”

We’re now months after the election, and Republicans have already identified a primary challenger for King in 2020, someone who they believe can keep his seat in the party’s hands. Hence the blossoming of conscience in McConnell, McCarthy and others. I lied before. I do get it. Pragmatism, expedience and the maintenance of power are the real monarchs of politics — and not just among Republicans.

But there’s even more than that behind the party’s sudden turn against King. As with most everything else in Washington at this cursed juncture, this is largely about Donald Trump.

Trump’s own racist behavior and remarks — including, in the run-up to the midterm elections, his proud embrace of the term “nationalist” — have emboldened the Steve Kings of the world. Many Republicans recognize that. And despite all the pride that they have swallowed since Trump’s ascent and all the principles that they have betrayed, many of them yearn to make a stand or at least a statement against white nationalism, for the sake of their party’s long-term survival and, yes, for the country.

They also want to say and do something right at a moment of so much wrong — wrong that they have abetted and must answer for. The government is shut down. The president fields understandable questions about whether he’s a Russian agent. With his ignorance and arrogance, he seems to be hauling the country to the brink of a disastrous international crisis. He degrades his office daily. And most of them mutely watch. They quiver in the face of the president’s wrath.