The Post details how aberrant and wrong and narcissistic Trump’s speech to the Boy Scouts yesterday was.

For 80 years, American presidents have been speaking to the National Scout Jamboree, a gathering of tens of thousands of youngsters from around the world eager to absorb the ideas of service, citizenship and global diplomacy.

In keeping with the scouts’ traditions, all eight presidents and surrogates who have represented them have stayed far, far away from partisan politics.

I had assumed that, without knowing anything specific about it, because after all, it’s the Boy Scouts – it’s not a set of people you would expect to be interested in the minutiae of Donald Trump’s political biography and it’s also not a set of people you have any business assuming are political allies. That’s not how Trump played it though. He made it all about him, and he treated them as rabid Republicans.

Franklin Delano Roosevelt used the occasion to talk about good citizenship. Harry S. Truman extolled fellowship: “When you work and live together, and exchange ideas around the campfire, you get to know what the other fellow is like,” he said.

President Dwight D. Eisenhower invoked the “bonds of common purpose and common ideals.” And President George H.W. Bush spoke of “serving others.”

For a brief moment at this year’s jamboree in West Virgina, President Donald Trump indicated that he would follow that tradition — sort of.

“Who the hell wants to speak about politics when I’m in front of the Boy Scouts?” he said.

It’s a miracle he didn’t tell them about his adventures in pussy grabbing.

Then, standing before all 40,000 of them, he bragged about the “record” crowd size, bashed President Barack Obama, criticized the “fake media” and trashed Hillary Clinton’s presidential campaign. In the lengthy 35-minute speech, the president threatened to fire his Health and Human Services Secretary if he couldn’t convince members of Congress to vote for the Republican health-care bill.

In short, he made a completely disgusting spectacle of himself.

At one point, he told a rambling story about a conversation he had at a New York cocktail party with a once-successful home builder who “lost his momentum.” The lesson, apparently: “You have to know whether or not you continue to have the momentum. And if you don’t have it, that’s OK.”

Throughout the address, Trump dropped in praise for “the moms and the dads and troop leaders” and thanked the scouts for upholding “the sacred values of our nation.”

And then quickly reverted to talking about himself and his political to-do list.

It was yet another example of Trump ignoring the custom that past presidents have dutifully observed in such public ceremonies. In his first full day in office, Trump bucked tradition at the CIA when he delivered a campaign-style speech in front of a memorial wall for fallen agency employees. In May, he used a commencement ceremony at the Coast Guard Academy to lament that he has been treated “more unfairly” than any other politician in history. And so it was at this year’s jamboree. Trump, who promised to be different than all the rest, was indeed just that, talking to the scouts in a way no president ever has.

His only interest is himself, and he’s so Theory of Mind-deficient that he thinks everyone shares that interest.