The most telling hot-mic moment of Barack Obama’s presidency came in March 2012 when he told Russian President Dmitry Medvedev: “This is my last election. After my election, I have more flexibility.”

The topic then was missile defense, but America and the world now see the full ramifications. Whether it’s dusting off an obscure provision to block oil drilling or using the United Nations to betray Israel, this is what maximum flexibility looks like. This is Obama being Obama.

Liberated from the pretense of respecting public consent and no longer forced to calculate the impact on Hillary Clinton’s campaign, Obama is rushing to settle scores and tie Donald Trump’s hands. It is an infuriating exit.

It is also a revealing one. The last-ditch actions help explain not only why Trump won, but also why a course correction was absolutely necessary for the nation. Obama’s cynical schemes are variations of “you can keep your doctor,” and Americans were right to show Democrats the door.

It’s also worth remembering that Obama promised to have Israel’s back, and that’s where he put the knife.

The silver lining in his fire sale, which also includes trying to make it more difficult for Trump to vet Muslim refugees, is that it offers a moment of clarity about the dangers of unrestrained power. Ultimately, it only serves itself.

And with Clinton promising to expand Obama’s executive overreach and with the likelihood that a Dem-packed Supreme Court always would say amen, our system of checks and balances would have been null and void if she had won.

Similarly, Obama’s boast that he would have beaten Trump had he been able to run illustrates the fundamental decency of George Washington. He easily could have won a third term, but chose, for the good of the country, to retire instead of emulating a monarch.

We can never know if Obama would have beaten Trump. We can only be grateful to the 22nd Amendment’s limit of two terms that he didn’t get the chance to try.

Against the crying-out-loud need for change, it is amazing that it still passes for brilliance in certain quarters to observe that, with Trump at the helm, we are entering uncharted waters. Thanks, Sherlock, but that was the central point of his election.

Voters across the spectrum, particularly those in the sagging middle classes and in the rusting middle of the country, no longer trust Washington, no matter the party label. They wanted a true outsider, somebody who, as Newt Gingrich put it, would kick over the table instead of angling for a better seat.

Apart from the gatekeepers and dead-ender partisans, those horrified by Trump’s crashing the cozy arrangements are suffering a version of Stockholm syndrome. If you believe that the world Obama leaves behind is the best of all possible worlds, it’s time to step away from the Kool-Aid.

The dreary economy, inflamed race relations, rising crime and falling quality of life in many communities — these are symptoms of decline. They always are, but Obama’s great success was in conning millions of Americans to believe this was the best they could hope for. Of course, he was aided and abetted by a liberal national media which functioned as a propaganda arm.

The same result is evident in America’s standing around the world. Distrusted by our allies and neither feared nor respected by adversaries, we are on the road to the worst possible outcome: global irrelevance. That, too, Obama and his media apologists falsely sold as a good thing.

None of this is easily fixed, but Trump has a unique opportunity. As Henry Kissinger told an interviewer, “He has absolutely no baggage. He has no obligation to any particular group because he has become a president on the basis of his own strategy and a program he put before the American public that his competitors did not present. So that is a unique situation.”

Mark those words, for Kissinger is describing in general terms a president that most Americans have longed for. They want a leader not hobbled by rigid orthodoxies, a doer instead of a talker and one free of special-interest debts.

In Trump, they have all that and much more. Hard-line Democrats know it, which is why they and their wingnuts are trying to destroy him even before he takes office. If he gets some early economic gains and builds momentum, Dems could be doomed to wander the political wilderness for years.

May it be so.

Albany always on sale

A Westchester Democrat is accusing Gov. Andrew Cuomo of trying to bribe the Legislature by agreeing to give members a pay hike if they vote for his agenda.

“We wouldn’t succumb to the governor’s attempt at bribery,” said Assemblyman Gary Pretlow.

“That’s right. You could say I used the word ‘bribery,’ ” he added.

On one hand, Pretlow’s fury is understandable. On the other, it’s not as if Cuomo just made up the idea that the Legislature is for sale.

Exposing ‘cam’-do Blas’ plot

Say this for Bill de Blasio: Nothing he does is subtle. Even his vote-buying is painfully obvious.

His latest scam is to give police officers a 1 percent salary bump if they volunteer to wear body cameras.

The offer was made to the police union, with the aim of enticing 1,000 cops to strap on the gadgets to record most of what is in front of them. It’s the first phase of a court-ordered program that will require all officers to wear the cameras.

De Blasio, of course, has a tortured relationship with most cops, with the bad blood starting when he turned his 2013 campaign into a nonstop bash of the NYPD. Even as mayor, he supported anti-police demonstrations, and the breach never fully healed after two officers were murdered just before Christmas in 2014. Many officers turned their backs on de Blasio at the funerals.

The cameras, although they can often resolve disputes in police favor, are being pushed by critics. That’s why most cops across the country resist them, and there are predictions that they will add to the “Ferguson effect” of cops pulling back from enforcement because the political class will abandon them at the first sign of controversy.

That pattern describes de Blasio perfectly, so he is forced to resort to a “bonus” to get cops to sign on. Especially during his re-election run, he doesn’t want the public to be reminded of his wars with the NYPD.

So he dips into taxpayer cash — and presto, tries to buy himself new friends. As I said, there’s nothing subtle about him.

Deli one-liner on wry

The Post’s delicious story on the end of the line for the Carnegie Deli included this gem from late owner Leo Steiner:

“Whaddya mean, ‘Is chicken soup good for you?’ You ever see a chicken with a cold?”