Donald Trump. Would that it were unnecessary to mention his name except, say, as a Viagra pitchman.

Despite such casting perfection, this isn’t intended as a metaphor for the man, though it is for the GOP. Cue sound of balloon losing vigor. The erstwhile party of Lincoln has rendered itself impotent by its clammy-handed embrace of the sad clown who made everybody laugh — for a while.

But the enchanted evening Republicans fantasized when they nominated the biggest goofball ever to enter the Oval Office sweepstakes is over. The clock has struck midnight, the carriage is ablaze; the golden-haired prince is a bloated chimney sweep ranting at rooftops. The party’s footmen, blind mice begging for scraps of mercy, scatter in search of cover.

Even Rep. Mark Sanford, the disgraced former governor of South Carolina, took to the quill, writing in a New York Times op-ed that he might no longer support Trump if he doesn’t produce his tax returns. Knowing with 99 percent certainty that this won’t happen, Sanford has carved a tiny escape hole in the baseboard for himself.

At the same time, talk radio hustlers who’ve more or less directed the GOP platform the past two decades or so, beginning with the Clinton administration, seem to be coming undone, floundering in the full-circleness of their anti-Clinton credo. Rush Limbaugh recently dissolved into a fit of giggles as he tried to pronounce the stupidity of Trump’s “softening” on immigration.

“Poor Ann,” he rasped, referring to Ann Coulter’s new book, “In Trump We Trust.” Anti-amnesty Ann, now on what she says may be the shortest book tour ever, has had to dial back her support for the GOP nominee if he doesn’t return to his hard-line deportation promise.

Quelle situation! The very “policy” undergirding Trump’s campaign suddenly became a negotiable talking point. Draconian Trump suddenly became Care Bear Trump: We need to be fair and maybe some should stay, he said. Then, just as suddenly — feeling the heat from his courtiers — he was back to dear old Draco. But of course he’s going to send them all back. Then, when they come back legally, if they do, they’ll have to pay taxes.

Because every ordinary billionaire does?

Trump was never going to build a wall, this columnist wrote. He was never going to deport 11 million people, she said. How exactly does one do this without sending armed forces to arrest Madre in the kitchen and Padre on the phone while their citizen-children watch in horror? Think back to the 2000 image of Elian Gonzalez’s “rescue” by masked, armed men, brought to you by the Clinton administration, let the record show.

For many of us scribes, Trump’s true nature and character were obvious from the start, not to mention 20 years before that. No degree of fleeting niceness (which, ahem, I gamely recognized in a recent column written for sport in response to a challenge) was going to make Trump less repugnant or more appealing for long. Predictably, he couldn’t sustain it. A person can only fake who he is for so long before the interior self emerges. Trump’s nice side, you can be certain, isn’t what appeals to members of the Ku Klux Klan or other white nationalist groups who find his ideas in sync with their own.

Trump’s calling Hillary Clinton a bigot when he is the bigots’ candidate should be viewed as the last gasp of a desperate nominee with no one left to insult. African Americans, previously ignored, are now in the sights of the flaming eye of Sauron.

This dark fairy tale was bound to end, if later than many expected. Sure, droves will vote for Trump no matter what — and we’ve learned that no-matter-what has elastic boundaries. His fans aren’t crazy or stupid, one is bound to say, and may justify their votes with concern for the future composition of the Supreme Court or for some variation of Trump’s shifting immigration policy.

But the truth is, most will be voting against Clinton, whom they dislike with such ferocity that they’d rather vote for Mickey Mouse — or even Donald Trump, master puppeteer and ringmaster of the Freakiest Show on Earth.

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