Jonathan Chait thinks Robert Mueller's investigation is in "mortal danger" because congressional Republicans have lost their moral compass in the Trump era. Trump's depravity, Chait believes, has rubbed off on other Republicans, and that's why they won't lift as finger in response to Mueller's dismissal:

As recently as a few weeks ago, Republicans were debating whether to shun [Roy] Moore or, should he win, vote to expel him from the Senate. They have settled on a course of action that had initially been off the map altogether: endorsing their lecherous ayatollah and providing financial support from the Republican National Committee.

What mattered most was that Donald Trump has contempt for any standards of conduct.... And no Republican who wishes to stay in office can afford to offend the president, who commands overwhelming support among the party base.

This was the dynamic last year, when a tape revealed Trump casually confessing to sexual assault, and it was briefly impossible to imagine that he could continue the campaign.... Then the incomprehensible became inevitable. The same thing happened in May when a Republican House candidate, Greg Gianforte, assaulted a reporter and then lied about it. Would Republicans denounce him? Expel him? It turned out they would do nothing. By the time Moore came along, the party’s moral sensibilities had been worn to a nub.

The next step in the sequence is almost insultingly obvious. Trump is preparing to shut down Robert Mueller’s investigation of Russian intervention in the 2016 election...

It is almost a maxim of the Trump era that the bounds of the unthinkable continuously shrink. The capitulation to Moore was a dry run for the coming assault on the rule of law.

"What mattered most was that Donald Trump has contempt for any standards of conduct"? No, that's not what mattered most, because the rest of the GOP has made its own contempt for standards of conduct clear for years. Trump may have accelerated the Republican Party's descent into amorality, but he didn't start it.

Remember that congressional Republicans never opposed the Bush administration's decision to build a prison at Guantanamo that mocked the notion of due process; long before Trump promised to send more "bad dudes" there, it was that nice Mitt Romney, in the 2008 campaign who promised to "double Guantanamo." Republicans defended Bush-era torture and illegal surveillance. Republicans were fully on board with Bush administration efforts to suppress the votes of blacks and other Democratic-leaning groups. Republicans shrugged when the John Roberts Supreme Court eviscerated the Voting Rights Act in 2013. Republicans launched an all-out assault on regular order in Congress when they held a Supreme Court seat open for a year starting in March 2016, months before Trump clinched the Republican presidential nomination. Republicans launched multiple Benghazi investigations against Hillary Clinton even though they could never find a genuine reason for outrage. I could go on.

If their initial response to the appointment of Mueller was that they'd raise hell if Mueller was fired, that was Republicans saying what they thought they had to say. Only the most naive person thought they really meant it.

Trump hasn't worn down congressional Republicans' moral scruples -- he's just showing them how much they can get away with.

Crossposted at No More Mr. Nice Blog