Now that Donald Trump has signaled that he believes Roy Moore should be the new face of the Republican Party on Capitol Hill, he has placed every one of his fellow Republican leaders in a tough position.

They must take a stand. That stand can be with Trump and Moore and a vision of a Grand Old Party that will embrace even its most reprehensible candidates as better choices than the most honorable Democrats. Or it can be with a vision not just of the GOP but of American politics as a higher endeavor that seeks to address rather than extend the nation’s challenges.

There is no middle ground.

Trump is clear about how he wants the Republican Party to define itself. In his view, it should place partisanship above principles—aggressively and unapologetically. The president is blunt:

Democrats refusal to give even one vote for massive Tax Cuts is why we need Republican Roy Moore to win in Alabama. We need his vote on stopping crime, illegal immigration, Border Wall, Military, Pro Life, V.A., Judges 2nd Amendment and more. No to Jones, a Pelosi/Schumer Puppet!

With his choice, Trump has made Moore, who stands accused of molesting teenage girls, a defining figure and a defining choice for top Republicans.

The more honorable of their number are refusing to go along.

The immediate former Republican nominee for the presidency, Mitt Romney, argues that

Roy Moore in the US Senate would be a stain on the GOP and on the nation. [Moore accuser] Leigh Corfman and other victims are courageous heroes. No vote, no majority is worth losing our honor, our integrity.

Senate majority leader Mitch McConnell (R-KY) says he still objects to Moore. But McConnell sounds soft as he says, “I had hoped earlier he would withdraw as a candidate. That obviously is not going to happen.” The Senate Republican leader says the chamber will have to seat Moore if he is elected on December 12, but suggests an ethics inquiry might yet hold the Alabaman to account. Now that Trump and his chief political enforcer, Steve Bannon, are firmly aligned with Moore and the politics of no apologies, however, the prospect that Moore could be expelled seems less and less likely.

So the way to stop Moore is on December 12, by backing the only candidate who can beat an unacceptable Republican, Democrat Doug Jones. Responsible Republicans recognize this. Senator Jeff Flake (R-AZ) has signaled his support for Jones—going so far as to post an image of the $100 check he wrote to support the Democrat. On the check, he wrote: “Country over Party.”

That statement does not make Flake a hero. It should be the baseline standard for Republicans who ask that Americans see them as honorable. Unfortunately, the most prominent and powerful Republican after Trump is House Speaker Paul Ryan, the party’s 2012 vice-presidential nominee and the man who follows Vice President Mike Pence in the presidential line of succession. Like McConnell, Ryan said several weeks ago that Moore should “step aside” as the Republican Senate nominee in Alabama. But Moore is not going anywhere.

Ryan, the most partisan Republican in Washington, has offered no indication that he will follow Jeff Flake’s lead—or even that of his former running-mate, Mitt Romney. What Ryan fails to recognize is that it is no longer enough to criticize Moore. The “country-over-party” position that Flake has outlined requires an affirmative act. Republicans who refuse to endorse Doug Jones are quietly lining up with Donald Trump, Roy Moore and a partisanship that is without honor.