If Bernie Sanders wins the Democratic nomination, our deranged and grotesque authoritarian crime-boss president will almost certainly be re-elected, and this country will be saddled with a political and cultural tragedy of increasing proportions.

This is not theory, not maybe — it’s real. How can Democrats be so rock stupid as to not see the tragedy that’s currently unfolding and taking shape? The republic is splitting, cracking apart. The end of civic sanity and reason is nigh. And it’s like we’re all covered in a kind of slow-motion glue.

The untested Sanders (a virtual babe in the woods on the national stage) is electoral death. He won’t just get knifed and bloodied by the Trump smear machine — he’ll probably get creamed a la Jeremy Corbyn and George McGovern.

Can anything prevent this nightmare? Not if African-American voters have anything to say about it, and of course they will starting with the South Carolina primary.

Pete Buttigieg recently connected with moderate suburban Iowans, and could theoretically do the same countrywide in the general. But AAs (particularly your older-demo homophobes) are apparently determined to sit on their hands rather than support him. (One more time — thanks, guys!) And of course Bernie bruhs and other progressives hate Pete’s guts. Except Pete or someone like him — a sensible, practical-minded, non-scary moderate liberal or left-centrist — represents the only shot at beating Trump. Who else could become the prime banner-carrier for this kind of approach at this point? Biden, Warren and Klobuchar are too low in the polls — they have no serious heat. Ditto Bloomberg and Steyer. It’s down to Pete v. Bernie, except Bernie is more or less Corbyn.

Filed on Sunday, 2.9 by London Times correspondent Josh Glancy: “At a ‘politics and eggs’ event on Friday morning in Manchester, New Hampshire, Bernie Sanders faced a friendly crowd, who applauded his familiar spiel about the ills of Wall Street, Donald Trump and big pharma. But one voter, Lenny Glynn, had a question.

“’There’s a lot of people in this room that share your anger, your anxiety and your rage,’ Glynn said. ‘But there’s a question in a lot of our minds. Jeremy Corbyn, the leader of the British Labour Party, who is very similar ideologically and politically to you, just took them to the worst defeat they’ve had in half a century. How can you assure us that you would not face the same onslaught?”

N.Y. Times columnist Frank Bruni, filed on 2.8: “You can analyze Sanders and assess his prospects in terms of how liberal many of his positions are: the end of private health insurance, the dismantling of the Immigration and Customs Enforcement agency, free tuition at public colleges regardless of a student’s economic circumstances. By that yardstick he’s Corbyn, and, in my view, a hell of a general-election risk.”