What are their options?

Here are some things they know. Trump won the presidential nomination according to rules agreed in advance. Millions of their fellow Republicans have rightly or wrongly placed their faith in Donald Trump. If party leaders repudiate him, they’ll split the party—and probably end up with the smaller piece.

They also know that a fractured party will always lose on a much bigger scale than a united party. Since Ronald Reagan left office, eight presidential elections ago, the worst presidential election performance by a united party was the 45.6 percent gained by Michael Dukakis in 1988. The worst by a divided party: George H.W. Bush’s sub-Goldwaterian 37.6 percent in 1992.

When a presidential candidate loses big, moreover, the casualties can accumulate all the way down the ballot. Republicans lost 21 seats in the House in 2008, atop their 30-seat loss in 2006. They dropped 8 seats in the Senate, having already lost 6 in 2006.

And a presidential candidate is a party’s best fundraiser. The entire national campaign organization is built around him: voter identification, micro-targeting, get-out-the-vote efforts. There isn’t one bus to drive presidential voters to the polls and a second bus for down-ballot voters: It’s one ride per person, and if that person stays home to protest a presidential nomination, he or she is equally AWOL for members of Congress, governors, and state legislators.

Politicians may wish for better facts. But they have to work with the material at hand in hope of preventing even greater evils.

More F.S. Oliver: Nothing in politics is sadder than:

the man of sterling character whose genius is so antipathetic to the particular emergency in which he finds himself as to stupefy his thoughts and paralyze his actions. He drifts to disaster, grappling blindfolded which are beyond his comprehension, failing without really fighting.

Bad choices over the past decade by Republican political leaders opened the way to Donald Trump, yes. For a decade, Republican voters have signaled they wanted to protect Medicare, cut immigration, fight fewer wars, and nominate no more Bushes. Their party leaders interpreted those signals as demands to cut Medicare, increase immigration, put boots on the ground in Syria, and nominate another Bush. Outdated ideology and obstinate donors impelled elected officials onto a disastrous path. More ideology and more obstinacy won’t rescue them from the cul-de-sac into which they walked themselves.

Their task ahead, in the Biblical phrase, is to pluck the brands from the fire—rescue as much of their party as can be rescued—while simultaneously minimizing the damage to party and country by the nominee their rank-and-file has imposed on them. They need to maneuver so that Trump’s defeat is as solitary as possible, and so that he cannot shift the blame for the failure he has earned onto the heads of others. They have to be ready to rebuild the day after the election, sifting through the Trump wreckage for what is fruitful for the future, discarding what is toxic, seeking to redirect the energies of his angry followers in ways productive for normal politics.