(CNN) The public consensus among Republicans in Washington is clear: President Donald Trump is not going to fire special counsel Robert Mueller. But if he does, well, watch out!

For what, precisely, is another question. Over the past few days, with Russia probe chaos noises turned up to 11, the congressional GOP has offered -- and, in House Speaker Paul Ryan's case, "received" -- assurances that Mueller's job is safe. Ryan wouldn't reveal his source, but it's probably fair to rule out Trump's Twitter feed, which hasn't exactly been a font of affirmation.

The possibility that Trump would move to sack Mueller, something the White House insists isn't on the table, has been a point of anxiety since the former FBI chief's appointment last May. Part of that is on Trump, naturally, and his itchy Twitter finger. The country has for almost a year been an inflammatory "Fox and Friends" segment, followed by a tap-tap-tap-tweet away from a constitutional crisis. Now, as tensions ramp up and we begin to look around that corner, there's little to suggest congressional Republicans would, under any condition, stand up in opposition to Trump.

Not that they aren't talking. "If he tried to (fire Mueller), that would be the beginning of the end of his presidency," said the ever-quotable senior senator from South Carolina, Lindsey Graham, on CNN's "State of the Union." He was repeating his own past remarks, just about to the word , but he never addressed the prospect of Republicans in Congress moving a measure -- like, for example, the one he co-authored -- to protect Mueller.

That kind of bipartisan bill, of which there are two now languishing in the Senate, would ensure the probe ran its natural course, not so much in defiance but in legally enshrined ignorance of Trump's whims. Anyway, it ain't happening. At least not this year. On Monday, Senate Majority Whip John Cornyn, noting that any bill of that nature would eventually end up on Trump's desk, explained why.

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