The grotesque sexual misconduct involving Democratic politicians — from New York Gov. Andrew Cuomo to California Rep. Eric Swalwell — has finally put #MeToo to rest.

We were reminded of its demise when it was revealed that Maine senatorial candidate and socialist heartthrob Graham Platner had been discovered to possess a long social media history of crude and pornographic put-downs of women.

The demise of Black Lives Matter offers another example of a recurring left-wing phenomenon: movements that begin as moral crusades and end as self-parodies.

Almost every BLM cause célèbre has proved fraudulent, following a long tradition that stretches from Al Sharpton’s Tawana Brawley myth to the Duke lacrosse scandal.

The aftermath of the death of George Floyd did lasting damage to the country that still reverberates.

The current leftist habit of urban intersection takeovers, statue-toppling, name-changing, and violent demonstrations is a legacy of that summer of lawlessness.

Thousands of police officers nationwide were laid off in “defund the police” madness.

Faddish “critical race” and “critical legal” theories led to no-cash bail and the near-immediate release of hundreds of thousands of arrested violent criminals.

Our supposedly best universities, in Pavlovian fashion, dropped the SAT admission requirement and upped race-based admissions.

Administrators and bureaucrats soon created thousands of DEI positions across universities and corporations.

And the result was certainly not better race relations.

The episodes of existential psychodramas that come and go — after doing enormous damage to the nation — are nearly endless.

A number of US and international agencies and “experts” have now, mostly quietly, sighed that global warming was never really the existential danger that the Left swore would put “Earth in the balance” in a mere decade.

Nonetheless, once again, the toll has been enormous.

The left-wing, postmodern, globalist notion of a borderless utopian world that would fuel endless “diversity” has done so much damage to Western nations that even the European Left now fears its own political suicide from the vast influxes of often hostile illegal aliens.

Millions of unlawful and unvetted entrants crashed the borders, with no desire to integrate, assimilate or acculturate to their Western hosts. They’ve spiked crime, fueled antisemitism and ensured unsustainable social welfare costs.

The transgender frenzy was to be the Left’s next civil-rights crusade, as it constructed a new victimized class with reparatory claims against the guilty traditionalist majority.

Soon, an epidemic of teens began wondering whether they were in fact “trans” and pondering whether to undergo a battery of dangerous hormonal and chemical drug regimens.

What accounts for these bouts of periodic, collective and suicidal madness?

First, the craziness is almost always birthed in the contemporary, affluent and leisured West, which alone has the capital and resources to afford such freakish sideshows.

Second, the frenzies are usually the creation of the Left, predictably birthed in universities, the media and the bureaucracies.

They appear with familiar symptoms. The irredeemable, deplorable and “garbage” hoi polloi are supposedly too dense to be properly schooled and thus must be frightened to death in order to adopt agendas that otherwise appear to them as utterly insane.

Junk your natural-gas dryer and grill, or face massive floods on your coasts. Drop the SAT and defund the police or face endless race riots.

Hire thousands of race and gender commissars or be forever tagged as racists, sexists, homophobes and transphobes.

Open the border and let illegal aliens enter by the millions, and thus pay partial penance for “whiteness.”

The Left is correct that few Western voters will openly embrace the unpopular elite agenda of racial fixations, globalism, laxity on crime and degrowth environmentalism.

So, their long-term solutions have four predictable aspects:

1) Open the borders to create a more diverse, impoverished and needy constituency.

2) Create fake “working-class” pseudo-populist candidates like the pampered Graham Platner, the God-is-nonbinary “new Christian” James Talarico and, of course, the waxen effigy of ‘good ol’ Joe Biden from Scranton.

3) Destroy time-tested systems by seeking to demolish the Electoral College, the 50-state union, the Senate filibuster and the nine-justice Supreme Court.

4) Gin up these end-of-days, pseudo-existential crises whose solutions require massive new taxes, bigger government and more dictatorial elite managers.

One good sign of growing antidotes is that increasingly Americans, and indeed all Westerners, are saying no to green haranguers, gender and sex demagogues, the race-baiting industry, the open-borders conglomerate and ungrateful immigrants.

Their pushback might be summed up as: “We are no longer going to allow you to destroy ancient traditions that ensured our prosperity, security and liberty, and which were handed down to us by generations far better than your own.”

Victor Davis Hanson is a distinguished fellow of the Center for American Greatness.