Alabama’s Republican Senate candidate Roy Moore now stands credibly accused of sexually abusing multiple women, including a 14 year old, when he was a young man. If he steps aside rather than face voters in December, it will cut against the lesson every GOP politician in the country has learned over the past two years: that Republicans will confer impunity on one another as long as they survive their scandals.

It is no surprise that in condemning Moore, and calling on him to resign “if the accusations are true,” Republicans have drawn themselves a loophole large enough to house a Roy Moore welcome party next month. It is, of course, true that GOP leaders do not want to be tainted by association with a child predator, and would sing sweet relief if Moore voluntarily stepped aside and allowed another Republican to run in his place.

But most will make no firm demand that he bow out, let alone endorse his Democratic opponent.

If Moore presses ahead, this will be the reason. If he becomes senator despite the new revelations, he will have accomplished no more than Donald Trump did when he sailed to the presidency in the slipstream of GOP indifference to corruption, authoritarianism, and sex crimes. Even if Moore bails out of the race or loses, more Roy Moores will keep crawling out from under rocks and into Republican politics, until Republicans stop showing bottomless tolerance for lowlives, bigots, and crooks, so long as the lowlives, bigots, and crooks can win elections. They can not stem this tide until they reckon with the moral rot they embraced when they made their peace with the current president.

Party leaders aren’t just legislative strategists, policymakers, and campaign tacticians, but validators of moral behavior. They communicate through their own standards of conduct who is welcome and who is not. We can’t prove a counterfactual, but it is a fair guess that there’d be no Senate nominee Roy Moore if Republicans had dumped Trump before he claimed their nomination, or after his proclivity for sexual assault had come to light.

At the same time, Moore is a unique case. He’d been a fixture of Alabama’s religious right wing for years before he ran for senator and in a divided primary, he might have become the Republican Senate nominee even absent Trump’s takeover of the GOP. It’s the next round of GOP recruits that will teem with ethically abased charlatans and human scum, because Republicans have laid out a welcome mat for them.

Consider how ambitious right wingers have experienced Republican politics in the past decade:

• They spent the Obama years watching the right wing grift industry explode into a multi-billion dollar industry, conferring vast fortunes on predators, political and sexual.
• They watched those grifters become kingmakers in Republican politics, and even candidates for the presidency.
• Eventually, one of those candidates—a flamboyantly ignorant, racist, money-laundering scam artist with mob ties and an autocratic bent—rocketed to the top of the Republican presidential primary field. Republican leaders, and other Republican candidates, failed to coordinate in any way to prevent him from winning the nomination.
• With the unanimous backing of the GOP establishment, he accepted the nomination.
• A videotape surfaced in which he’s caught bragging about sexually assaulting women with impunity.
• Multiple women confirmed on the record that he assaulted them precisely as described in the videotape.
• Some Republicans withdrew their endorsements. Within days, nearly all of those Republicans reinstated their endorsements.
• He won the election.
• It turns out that to win the election, he conspired with foreign spies to sabotage his opponents.
• He immediately began using the presidency to enrich himself, by soliciting bribes and funneling government payments through his business entities.
• Corruption became pervasive in his cabinet.
• Republicans refused to conduct any meaningful oversight.

That is the backdrop against which Roy Moore’s sex crimes came to light. Some Republicans have admirably and unambiguously called upon Moore to step aside.

The allegations against Roy Moore are deeply disturbing and disqualifying. He should immediately step aside and allow the people of Alabama to elect a candidate they can be proud of.

— John McCain (@SenJohnMcCain) November 9, 2017

But the consensus view in Republican circles is that Moore should only step aside “if these allegations are true.” Republicans have made no effort to set forth what will satisfy them that the allegations are true, because they are trying to have it both ways. This is a hedge that tells us everything we need to know about how the Republican conference will press ahead, should Moore win and become a vote for the GOP agenda. It is another signal to future right wing vermin that their behavior will be excused if they can weather the storms of their own scandals.

And that lesson will ripple across right wing political culture, no matter how Moore responds to the firestorm surrounding him.

McConnell-aligned super pac Senate Leadership Fund — “There is no place in our party for sexual predators.”

— Tarini Parti (@tparti) November 9, 2017

Republican leaders will of course grasp for the high ground if Moore’s base of support collapses, but that ground is unavailable to them. Their ongoing alliance with Trump, another sexual predator, gives the lie to the notion that Republicans are drawing a moral bright line. Short of taking proactive steps to deny Moore the Senate seat, the unmistakable message will be that only sexual predators who can’t win are persona non grata in GOP politics. And even then, the moral turpitude they have already blessed will remain a magnet for other wicked men until they all atone for their sins and remove the source of the rot.