Mark Warner, ranking Democrat on the Senate Intelligence Committee, means well. He has tweeted "any attempt to remove the Special Counsel, pardon key witnesses, or otherwise interfere in the investigation, would be a gross abuse of power" and "all members of Congress, from both parties, have a responsibility to our Constitution and to our country to make that clear immediately."
Nonetheless, the Virginia senator also tweeted "I've said it before, and I am saying it again: firing the Special Counsel is a red line that the President cannot cross."
Saying it repeatedly, unfortunately, won't make it magically happen, though perhaps Warner meant that this President cannot cross a red line with Mueller any more than the previous one did with Syria, which meant nothing, notwithstanding helping defeat Hillary Clinton.
As Natasha Bertrand has noted, "Trump asked Comey for loyalty; asked him to drop the Flynn probe; fired Comey; pressured Sessions not to recuse; pressured Sessions to fire McCabe; pressured Coats, Rogers, Pompeo & multiple congresmen to say he wasn't under FBI investigation; and tried to fire Mueller."(He also fired Sally Yates.)
Trump calls the investigation a "witch hunt" and has such members of Congress as Senators Cornyn and Johnson criticizing the FBI and Representative Trey Gowdy undermining the FBI. Devin Nunes has beeen such a toady for Dear Leader that if he isn't being paid a salary as a member of the President's communications team, he should sue. (Meanwhile, Martin Luther King's birthday came and went without a hint of criticism from them over FBI surveillance of the Reverend Dr.; can't imagine why.)
But the best evidence that firing Mueller is no "red line" that cannot be crossed ironically comes from the Senator who at one time seemed exorcised by the possibility. The Daily Beast's Betsy Woodruff reports
Sen. Thom Tillis, a North Carolina Republican in his first term, made headlines over the summer when he signed on to legislation with Sen. Chris Coons (D-DE) that would have shielded Mueller from being fired. But Tillis has largely abandoned the push to move that legislation forward while conceding that the bill doesn’t have the support to get through Congress. His office says he still supports the bill, but that the matter isn’t urgent since Trump says he doesn’t plan to fire Mueller....
On Thursday night, The New York Times reported that Trump tried to fire the special counsel last summer. (Tillis spokesperson Daniel) Keylin told The Daily Beast that despite the revelation, Tillis continues to trust that the president isn’t planning to fire Mueller, who is leading an investigation into potential coordination between the Trump campaign and the Russian government during the 2016 election.
The Senator is blowing smoke up our posterior or, as the commercial puts it, our kiester (Wisconsin). Woodruff further explains
the dialing back of the Senator's support is significant. Unlike Graham, who veers between bashing Trump and golfing with him, and Coons and Booker—both Democrats—Tillis could bring the legislation to shield Mueller serious bipartisan bona fides. When he introduced his bill, Tillis similarly didn’t believe that a firing of Mueller was near, but he pitched the legislation as a precautionary measure.
“I don’t have any evidence to suggest the White House had any intention of doing it [firing Mueller], but it’s a helpful way for us to take it off the table,” he explained.
Now the proposal has been all but taken off the table- not because firing Mueller is a longshot but because it would put congressional Republicans into a bind. They would have to choose between giving to Trump a pass on an act which would instantly incite massive demonstrations nationally or angering the President's base, much of which is unyielding. Republicans who would vote in favor of Tillis-Coons also would be subject to Trump's angry and derisive tweets, and Republicans don't like to get their feelings hurt.
And then there is the matter of taxes for the wealthy, which Sarah Ellison described in August as it pertained to Paul Ryan, who had condemned Donald Trump for his 7/15 charge that Mexico was sending "their rapists" to the USA; allegation that Judge Curiel was biased because his descendants were from Mexico; travel ban; and comments on the Access Hollywood tape. Nevertheless the House Speaker has made a
bargain (which) is clear—it’s the one spelled out by Grover Norquist back in 2012, when Norquist defended the choice of Mitt Romney by saying he’d also have endorsed a monkey, a plate of lasagna, or a potted plant. All Norquist wanted was “a Republican with enough working digits to handle a pen” to sign legislation. Ryan wants to gut the safety net for the poor and cut taxes for the wealthy, and believes that with Trump he can do that. He said recently that he had dreamed of cutting Medicaid since his keg-drinking days. Having Trump’s digits on the Resolute Desk—whatever the existential risk to the principles of the country as a whole—is a small price to pay.
Of legislation protecting Robert Mueller, Maine Republican senator Susan Collins in December remarked "I haven't seen the need for that because I really don't think the President is going to fire Mr. Mueller. But certainly the introduction of the bill sends a strong signal." It certainly did. And its virtual withdrawal has sent an even stronger one.