Sen. Patrick J. Toomey (R-Pa.). (Christopher Dolan/The Citizens’ Voice via Associated Press)

WHEN THE republic was in danger, where did you stand? History will ask that question of Republican leaders who knew that Donald Trump was unfit to be commander in chief.

Some said so, despite possible political risks. Sen. Ben Sasse (Neb.), Sen. Jeff Flake (Ariz.), Sen. Lindsey O. Graham (S.C.), former Massachusetts governor Mitt Romney and former high-ranking officials such as Brent Scowcroft, Colin L. Powell, Henry M. Paulson Jr., Michael V. Hayden and Robert M. Gates did their best to help Americans understand the risk of electing an ignorant, thin-skinned man with no relevant experience. Scores of respected former ambassadors and assistant secretaries also spoke out. Meanwhile, other senior statesmen were quiet; George P. Shultz and Henry A. Kissinger, for example, said only that they would endorse neither candidate. Their voices could have made — could still make — a difference. So could the voices of former presidents: Though there have been hints that former presidents George H.W. Bush and George W. Bush support Hillary Clinton, they have not taken the public stand their nation needs.

Many current Republican “leaders” tried various strategies to have it both ways. House Speaker Paul D. Ryan (Wis.) endorsed Mr. Trump but periodically tut-tutted at the GOP nominee’s racism and misogyny. Senate Majority Leader Mitch McConnell (Ky.) endorsed him and then did his best to pretend Mr. Trump did not exist. Former opponents such as Sens. Marco Rubio (Fla.) and Ted Cruz (Tex.) passionately explained why Mr. Trump should never occupy the White House, then endorsed him. Sen. Rand Paul (Ky.), the libertarian tribune of a new, more modern, open-to-minorities-and-youth GOP, called Mr. Trump “a delusional narcissist and an orange-faced windbag,” adding that “a speck of dirt is way more qualified to be president.” Then he endorsed the nominee.

Some GOP lawmakers denounced Mr. Trump after The Post released a video in which he bragged about sexually assaulting women — and then scurried back to Mr. Trump’s side when they discovered that abandoning him might come with a political price. Rep. Jason Chaffetz (Utah) withdrew his endorsement in response to the video, saying he could not look his 15-year-old daughter in the eye having endorsed him, then announced that, though he “will not defend or endorse” Mr. Trump, he will vote for him. Sen. Mike Crapo (Idaho) called for Mr. Trump to leave the race, then declared that voters “must” elect the GOP nominee. Rep. Joseph J. Heck, running for the Senate in Nevada, endorsed then un-endorsed Mr. Trump and has since been essentially silent about his decision-making.

Historians may find themselves most mystified by the politicians who refused to say anything. Sen. Patrick J. Toomey is running for reelection in Pennsylvania. He is asking voters for their trust. Yet he will not tell them for whom he will vote in the presidential election. Apparently he believes, as Mr. Heck insisted last week, that his vote is a “personal decision.”

No, it is not a personal decision; it is a test of judgment. The politics may be difficult for down-ballot Republicans, but the choice, on the merits, is not. Mr. Trump is a menace to the nation. Many high-ranking Republican officials understand this. Some chose to act forthrightly in this knowledge.

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