Several prominent Republicans seemed to collectively breathe a sigh of relief yesterday. After spending months kicking around a series of talking points intended to defend Donald Trump in his Ukraine scandal -- some of which were contradictory, some of which were laughable, each of which was woeful -- many in the party finally started to settle on the one assertion that can't be discredited or debunked:

Republicans no longer think it matters whether the president is guilty.

For months, the president's GOP allies fought a losing battle, challenging the available facts, insisting Trump did not do what the evidence said he did. But on Monday night, during the impeachment trial, Alan Dershowitz stood on the Senate floor and argued, in reference to the reported revelations from John Bolton's book, "[N]othing in the Bolton revelations, even if true, would rise to the level of an abuse of power or an impeachable offense."

It was as if a lightbulb flickered on in the Republican cloakroom. The Washington Post reported overnight:

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"Let's say it's true, okay? Dershowitz last night explained that if you're looking at it from a constitutional point of view, that that is not something that is impeachable," Sen. Mike Braun (R-Ind.) told reporters Tuesday morning. "Alan Dershowitz said it was not" impeachable, said Sen. Roy Blunt (R-Mo.), a top ally of Senate Majority Leader Mitch McConnell (R-Ky.). "And I don't disagree with that." The ramifications are striking and could have long-term implications. The argument suggests senators believe a U.S. president can use taxpayer dollars to pressure an ally to investigate an American citizen who happens to be challenging him for president, without any repercussions.

A CNN report added, "A growing number of GOP senators are now acknowledging that President Donald Trump may have leveraged US military aid to Ukraine in exchange for an announcement of investigations that could help him politically -- but they contend that even that conduct does not warrant removal from office or hearing from additional witnesses."

It'd be an overstatement to suggest every congressional Republican has embraced this new posture, but the list of prominent GOP officials touting the new talking point isn't short. It includes Senate Intelligence Committee Chairman Richard Burr (R-N.C.), who argued, "[E]ven if the president said [to John Bolton that he was withholding military aid in exchange for investigations], it does not raise to the level of removal from office."

The party's indifference seemed liberating. If Trump's culpability is no longer relevant to his GOP acolytes, then the answer to every question could be effectively the same: "It doesn't matter."

Even if every allegation is true, even if the president did exactly what he's accused of doing, even if he abused the powers of his office in the precise way Democrats claim, much of the Republican Party has convinced itself, quite suddenly, that the presidential misdeeds simply don't meet the arbitrary threshold for importance.

And if the allegations are no longer relevant, then the trial is no longer relevant, and the need for witness testimony is no longer relevant. Dershowitz effectively handed the GOP a key to get his client out of this mess, and several Senate Republicans rushed to use it.

As a substantive matter, the party's new posture is indefensible. Trump's abuse of power was staggering on a historic scale and, according to Congress' independent watchdog, blatantly illegal. For lawmakers to say it's perfectly permissible for a president to ignore the law, withhold congressionally approved aid to a vulnerable ally, as part of an extortion scheme the president hoped to use to cheat in an election, is madness.

But as of this morning, much of the Senate Republican conference has decided the smart move is to simply not care. The more Democrats point to evidence of Trump's misconduct, the more GOP senators will reply, "So what?"

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