Twenty-two years now: For all that the anniversary can bring so many of us back to that bright September morning like it was yesterday, ever-more Americans have no memory of 9/11 at all.

Today’s college graduates were born after the planes hit the Towers, the Pentagon and that Pennsylvania field. Most barely even recall the Iraq War, for all that it lingered on for years.

What was once a universal experience — everyone could talk about where they were that day and how it changed their lives — is becoming history.

“Never forget” takes on a whole new meaning.

We still have the Tribute in Light, the somber ceremonies at Ground Zero and elsewhere; the museum and the memorials.

Cable broadcasts an ever-larger range of documentaries on the events of that day, the runup to it and the aftermath.

We retell the tales of the heroes: Todd Beamer & Co. charging the United 93 cockpit; Stephen Siller’s run from Brooklyn to the World Trade Center site; Rick Rescorla getting his 2,700 people out when the attack he’d long warned would come finally hit.

On the other hand: America answered 9/11 by liberating Afghanistan from the regime that sheltered the al Qaeda attackers — and now President Joe Biden has handed it right back to the Taliban.

He’s observing Monday’s anniversary in Alaska, and his Pentagon lawyers are trying to strike a plea deal with attack-mastermind Khalid Sheikh Mohammed and the other top plotters.

This isn’t healing, but a willful effort to deny and forget 9/11’s lessons.

So, for those of us who can:

Recall the shock when the first plane hit at 8:46 a.m., then the second at 9:03 — and we all realized it was an attack on America even before the Pentagon got hit at 9:37 and we all braced for what might be coming next.

Remember the weeks of rescue and recovery efforts, with Lower Manhattan blocked off and all the bulletin-boards full of heartbreaking “Have you seen” signs.

Mourn the near-3,000 lives lost, including the FDNY’s 343.

And don’t forget how the nation (all too briefly) united in sorrow, shock and resolution: For all our divisions, we truly are one people.

For those who can’t remember: Learn.

And know that the fanatics attacked America not for anything we’d done, but for what we are: overwhelming evidence that freedom works.

That a nation conceived in and dedicated to individual liberty can prosper beyond previous comprehension — a beacon to the world and its savior in the 20th century’s three global battles against evil.

These particular fanatics were dedicated to one specific, twisted version of a great faith, but those who seek to crush human souls in the name of any ideology — or for any other reason — will always see our country as the ultimate enemy.

Time heals; it’s unbearable to live with horror constantly in the forefront of your mind.

But as 9/11 becomes history, heed the words of George Santayana: “Those who cannot remember the past are condemned to repeat it.”