To Republicans who hope to emerge from the Donald Trump fiasco with any shred of political viability or self-respect, I offer some unsolicited advice: Run, do not walk, to the nearest exit.

I’m speaking to you, House Speaker Paul Ryan. And you, Sen. John McCain. And you, Senate Majority Leader Mitch McConnell — along with so many other elected Republicans and party stalwarts. You are not fools. You are well aware that the erstwhile Party of Lincoln has nominated for president a man wholly unfit to hold the office.

I realize that puts you in a tough spot politically. Breaking with the party’s standard-bearer, chosen by voters in primaries and caucuses, would surely mean short-term pain. For some of you, it could be politically fatal. But sticking with Trump, as far as I can see, will almost surely be worse — for you, for the party and, potentially, heaven forbid, for the country you have sworn to serve.

You’re taking a position that is indefensible on both philosophical and real-world grounds: begging Trump to pretend to be sane and competent until Election Day.

“Anybody who is horrified by Hillary [Clinton] should hope that Trump will take a deep breath and learn some new skills,” Newt Gingrich told The Post on Wednesday. “He cannot win the presidency operating the way he is now.”

The Washington Post’s Philip Rucker explains how unusual it is that Republican presidential nominee Donald Trump is withholding his endorsements of House Speaker Paul D. Ryan and Sen. John McCain (R-Ariz.) in their primary races. (Bastien Inzaurralde/The Washington Post)

This week, Republicans, your calls for Trump to tone it down shifted into panic mode. Apparently you thought it was a bad idea for him to attack a Gold Star mother who lost her Army captain son in Iraq, then clumsily contrive to keep the story alive for nearly a week. You thought Trump’s pointed refusal to endorse Ryan and McCain in their primaries, even though both are supporting him, might not be the best way to foster party unity. You thought perhaps that while there are many things a candidate might say at a rally to win friends and influence people, “Get the baby out of here” is not one.

Your response is to hope against hope that someone will persuade Trump to feign rectitude for the next three months. But think of the implications of imploring him to look and sound “presidential.” You know full well how out of control and unbalanced he is; you just wish he’d do a better job of conning voters into thinking he can be trusted with the nuclear codes. Shame on you, Republicans, for encouraging such a dangerous ruse.

And in any event, it should be clear by now that Trump cannot or will not pretend to be a normal candidate. How many resets have there been already? Let me make a bold prediction: Within the next week or so, Trump will give a stilted, non-crazy, teleprompter-aided speech. Supporters will rejoice that the campaign has finally turned a corner. And then, a few days later, some perceived slight will have Trump once again tilting at windmills and baying at the moon.

Republican officials and party leaders, you got into politics because you believed in certain principles. I may disagree with many of your views on policy, but I do not question your sincerity. I firmly doubt, however, that Trump knows what the word “sincerity” means.

You believe in conservative values; he manifestly does not share them. You believe in sound, prudent fiscal management; he runs his real estate empire like a pirate, trailing bankruptcies in his wake. You believe, generally, in a strong defense posture; he is open to handing Crimea and perhaps the Baltics to Vladimir Putin. You believe in limited government, answerable to the people; he describes a bleak, failed America in his acceptance speech and proclaims that “I alone can fix it!”

Republicans, you are aiding and abetting a latter-day Juan Perón in his quest for power. You know that he believes in no coherent policy agenda beyond his own self-proclaimed greatness. You see how unhinged he becomes when anyone challenges him. You know what a grave risk it would be to have a man like that in the Oval Office.

You may be making the calculation that tepidly supporting the party’s nominee will leave you best situated to help revive and reform the GOP after Trump is soundly defeated by Clinton. Judging by this week’s polls — Clinton has leapt into a solid lead — your bet on the election’s outcome may be sound.

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But even if he loses, Republicans, Trump will leave a lasting stain. If you tell us such a man should be president, why should the nation ever believe anything else you say?

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