Senate Majority Leader Mitch McConnell finally made a choice in the exploding scandal surrounding Roy Moore, and his Senate Republican caucus thus far has followed suit. That newfound unity will undoubtedly lead to a rift within the rank and file of the party, and more reminders of candidate-recruitment fumbles in past cycles that cost the GOP dearly. But the choice itself is not just inevitable — it's also a rare moment where long-term thinking prevails over short-term consequences.

Four women came forward last week to accuse Moore of sexual misconduct nearly 40 years ago. The Washington Post published an extensive report with 30 sources for its allegations that Moore had dated teenagers while in his early 30s. One woman claimed that Moore had fondled her when she was 14 after taking her to his house in the woods, which she described in some detail.

Moore denied all of the allegations, and at first most Senate Republicans held off from making a choice on their nominee for the Dec. 12 special election for the Senate opening created by Jeff Sessions' ascension to attorney general. With the exception of John McCain, who immediately called for Moore to withdraw from the race, the rest of the Senate Republican caucus called the allegations disqualifying — "if proven." Members such as Mike Lee, Rand Paul, and Ted Cruz kept their endorsements in place, waiting for Moore's response.

That came in a Friday interview with Fox News host Sean Hannity, and it didn't go well. Hannity pressed Moore for explanations for why several women told similar stories, and Moore offered answers that didn't exactly build confidence in his insistence that the Post's story was a smear job. Moore flatly denied ever knowing Leigh Corfman, the then-14-year-old girl who accused him of fondling her, but when it came to two other then-teenage women cited in the Post article, Moore admitted knowing them. Hannity pressed Moore on whether he dated teenagers while in his 30s, to which Moore at first replied "not generally, no," but later said, "I don't remember ever dating any girl without the permission of her mother."

After that, the "if proven" caveat began disappearing. Lee withdrew his endorsement and called for Moore to withdraw from the race. Others followed suit over the weekend, and finally on Monday, McConnell added his voice to the calls for Moore's withdrawal. "I believe the women," the Senate majority leader declared, just a couple of hours before another woman came forward to accuse Moore, this time of a more violent attempt at sexual assault.

Beverly Young Nelson told the story of her assault in a Monday press conference with her attorney Gloria Allred, alleging that Moore groped her when she was 16. She also accused Moore of attempting to force her into oral sex in the same incident until he finally gave up and pushed her out of her car. Nelson told the press that she knew Moore as a regular customer at the diner where she worked as a waitress, and that he'd flirt with her there. Nelson produced her high-school yearbook from her sophomore year, which contained a Christmas greeting "to a sweeter more beautiful girl I could not say," signing it "Love, Roy Moore, D.A." and dating it on Dec. 12, 1977.

Needless to say, it's quite unusual to see a district attorney's signature in a high-school yearbook belonging to an unrelated teen girl.

Nelson stressed that she and her husband both voted for President Trump, and that her allegation "has nothing whatsoever to do with Republicans or Democrats. It has everything to do," she continued, "with Mr. Moore's sexual assault when I was a teenager."

Politics might not be on her mind, but one can't say the same for McConnell and the Republican Party. In the immediate future, they face the loss of an important seat in the Senate at a time when McConnell has found unity among his 52 members already in short supply. Perhaps if Moore bowed to pressure and dropped out, the state GOP could petition to have its endorsement of Moore removed from the ballot, maybe in the hope of putting together a write-in campaign for interim Sen. Luther Strange, who Moore beat in the primary.

Of course, Moore could stay in the race. He might even still win it, though it appears he would be very lonely in Washington. The chair of the GOP's Senate campaign committee said on Monday that even if Moore wins, senators should vote to expel him because "he does not meet the ethical and moral requirements of the United States Senate." The Republican Party clearly wants nothing to do with Roy Moore. And they are right to feel that way.

While the standard for criminal prosecution remains guilt beyond a reasonable doubt, and a preponderance of evidence for civil judgments, political assessments rely on judgment of character in relation to public trust. That looks to be an insurmountable obstacle for Moore. Whether or not he assaulted or molested teenaged girls, just the admission of pursuing and dating teenagers while serving as a 30-something DA will justifiably have voters wondering about his character. Republicans in the Senate have clearly concluded that Moore is doomed, and that they want as much distance from him as possible.

Still, it's difficult to view this entire episode apart from the tensions within the GOP that produced Moore's nomination in the first place. Moore ran against McConnell and the so-called Republican establishment and with the support of populist activists, most notably former White House adviser Stephen Bannon. McConnell has no investment in Moore beyond trying to retain his seat for the GOP, and Moore's failure would be yet another example of the lack of vetting in grassroots–drafted candidates that ran against traditional recruits, recalling the failures of Sharron Angle, Todd Akin, Richard Mourdock, and Christine O'Donnell in previous Senate contests.

But even beyond this election, McConnell and others in the Senate have turned to a longer-term political calculus. Sexual harassment and assault scandals have finally broken through to the center of debate, with accusations roiling centers of power in Hollywood, the media, and politics. The cultural paradigm has shifted enough for victims to feel more confident about exposing their alleged attackers, and the sheer volume and pattern of accusations lends more credibility in the public square. Attempting to defend and ally with Moore, especially as more accusations emerge, would tarnish the Republican brand for more than just a special-election cycle.

The world has changed. "I believe the women" has become more of a cultural default in the wake of Harvey Weinstein, Brett Ratner, Mark Halperin, et al when it comes to holding people accountable for abuse. In the end, Nelson will be proven correct: It's not about Republicans and Democrats, but about abuse and silence. Republicans and Democrats both have to choose whether to circle the wagons or promote accountability. In this case, even if it means the loss of a seat for a short time, McConnell and the GOP have chosen wisely.