We gather together on this solemn anniversary in a spirit of mourning and peace.

But this is also a time of unspeakable shame.

As we remember the nearly 3,000 souls who were butchered on American soil 14 years ago by Islamic terrorists bearing not a speck of decency or humanity, we must also remember what we have lost. And it is great.

In the days and weeks following Sept. 11, 2001, we were a nation united in agony. We bore a common resolve to defeat the forces of evil that hit us, and hit us hard. “Never again!’’ we cried in unison. I remember walking down a New York City street, debris still swirling in the air from the destroyed World Trade Center, and seeing women and even men hugging heroic cops, firefighters and other first responders.

Now, one is just as likely to see a man or woman in uniform spit upon or cursed at by the very people whose lives they protect every day.

We have transformed into a fractured society, paralyzed by leftist propaganda and lock-step political correctness. Many Americans, from those studying on university campuses to a baseball analyst for ESPN, are being bullied into submission or brainwashed into believing that our enemies are nothing more than misunderstood souls, justified in mass slaughter because of this nation’s imperialist policies.

And this disgraceful display makes me sick.

Nowhere is this suicidal trend more evident than in the treatment of cops. The alleged mistakes of a few — the shooting deaths of unarmed African-American men — have changed police into the enemy, according to some among us.

Anti-cop demonstrations included last year’s insane “die-in’’ on the steps of New York City Hall to protest killings, including the alleged chokehold death in police custody of Eric Garner, and to malign a Staten Island grand jury for failing to indict the officer involved.

Rather than work toward improving understanding between law-enforcement officers and the citizenry, useless members of the City Council joined activists and clergy members in lying on the steps outside the seat of local government in a depressing display of anti-cop hysteria.

America-loathing has risen to a new level on university campuses around the US. A freshman-level English course called “The Literature of 9/11’’ features writings from the perspective of Islamic butchers, as Paul Sperry, a visiting media fellow at the Hoover Institution, wrote in a piece published in The Post.

The highly ranked University of North Carolina at Chapel Hill is just one institution that has adopted the ugly curriculum (the University of Maryland is another), taught by associate English professor Neel Ahuja. He has written that the depiction of 9/11 terrorists as “monsters’’ is an attempt to “animalize’’ them as insects and to justify “squashing’’ them in a “fantasy of justice.’’ (I know whom I’d like to squash.)

UNC College Republicans recently sent a letter of protest to the school’s chancellor which, unsurprisingly, had no effect.

At ESPN, former star Major League pitcher Curt Schilling, a baseball analyst for the sports TV network, last month was suspended from covering the Little League World Series and a baseball game, then later pulled off the air for the rest of the baseball season.

His offense? Retweeting this message, along with a picture of Adolf Hitler doing the Nazi salute: “ONLY 5-10% OF MUSLIMS ARE EXTREMISTS. IN 1940, ONLY 7% OF GERMANS WERE NAZIS. HOW’D THAT GO?’’ Then he added these words: “The math is staggering when you get the true #s.’’

He quickly pulled down the tweet, removed the post from his Facebook page and apologized. But he’d already violated the concrete rule against criticizing — pretty much any group. Schilling then complained in an e-mail he sent to a writer about negative coverage on a sports Web site, which gave ESPN an excuse to kick him to the curb through October. Mind you, Schilling went off not on all Muslims, but on the minority who are extremists. Last time I checked, it was permissible to express hate and fear against savages such as the 9/11 attackers.

I guess I’m still living in 2001.

Recent initiatives from political liberals threaten to tear us apart.

The Obama administration’s wrong-headed nuclear deal with Iran, almost certain to survive Congress, threatens the existence of our great Middle Eastern ally, Israel.

I hope that, one day, we’ll look back on these times of America-bashing and capitulation to terrorists as shameful and temporary. That day can’t come soon enough.

Terrifying ‘zombie’ government

It’s not all about people-munching. I see AMC TV’s hit show “The Walking Dead’’ and the new prequel series, “Fear the Walking Dead,’’ as allegories of government paralysis and official incompetence.

Fictional humans in the shows demonstrate that when institutions collapse, the electrical grid goes down, Fresh Direct stops delivering and brain-eating ghouls rise up, while some still-breathing people survive — and thrive.

Set in soulless Los Angeles at the dawn of the zombie apocalypse that’s in full swing in “The Walking Dead,’’ “Fear the Walking Dead’’ smashed cable-TV ratings for its first two episodes.

Another is set to air Sunday. I expect that devotees of the zombie genre will continue multiplying like walkers.

Yes, rein in this parade!

I was appalled to learn that shootings have marred the annual West Indian Day Parade in Brooklyn, and related events, in 2003, 2005, 2011, 2013, 2014 and 2015.

Two people were stabbed to death in 2012. In 2013, a 1-year-old boy sitting in his stroller was killed by a bullet meant for his father!

New York City police sources complained to The Post that NYPD brass looks the other way at the carnage. Cops have been forbidden “from making arrests, no matter what we saw, because they didn’t want riots,’’ said an officer.

There were three stabbings this past Monday, one fatal. Four people were shot, including Carey Gabay, 43, a Harvard-educated lawyer for Gov. Cuomo, who is first deputy general counsel to Empire State Development.

Gabay — in critical condition in a coma — was shot in the head in what cops believe was cross fire between rival gang members after attending a predawn party.

But city Police Commissioner Bill Bratton dismissed calls to ban preparade events. Make it safe, Commish, or stop the party.

Cop tackle way out of bounds

Former tennis star James Blake, 35, who is biracial, rejected the idea that he’d been a victim of racism by white New York City Police officers.

“This was a case of excessive force. You’re not making it about racial profiling?”

interviewer Robin Roberts said to him Thursday on ABC- TV’s “Good Morning America.”

“No, Blake said.

Blake was thrown to the ground and cuffed briefly, then released, after being mistaken for a criminal at his Manhattan hotel while waiting for a ride to the US Open in Queens.

No one — of any race —should be subjected to excessive force by cops.