Sixty percent of Americans with dementia take off in what experts call ‘wandering.’ If not found within 24 hours, up to half of all wanderers suffer serious injury or death.

My father went missing sometime on the morning of Dec. 2.

Within hours, I was searching his empty house along with the Freehold, New Jersey, police. The beige Honda Civic wasn’t in the garage.

At 88, my dad is one of 5 million Americans who suffer from dementia. Above all things, he values his independence, vowing to die in the house he shared with my mom after they left Brooklyn 25 years ago, declining offers to live with either of his sons.

So, caretakers check in daily, cleaning up and watching “Bonanza” reruns with him. I make the 90-minute drive as often as I can.

On my dad’s runaway day, his first ever, I noticed that he took his wallet. He never carries the cellphone my brother gave him.

I showed iPhone pictures of my father to people at his local haunts — Stop & Shop, Dunkin’, Panera. “He wasn’t here today,” said a Panera employee. “I’ll pray for him.”

Hours went by without a word. The state police issued a Silver Alert. Radio and TV stations received my dad’s description, and his driver information was flashed on highway message signs.

He has a Combat Infantry Badge emblem on his license plates, a distinction of pride for a Korean War veteran who grew up wanting to be an actor and a singer, but instead became a dream-denying bricklayer to pay for marriage and kids.

The experts call it “wandering,” what my dad did. Sixty percent of Americans with dementia take off like this. If not found within 24 hours, up to half of all wanderers suffer serious injury or death.

As time ticked by, my wife, Andrea, joined a Freehold Facebook group to send out the word. Around 300 people responded, some of them saying they were getting into their cars and looking for my father themselves in the cold night.

Scrambling to figure out where my dad could be, I checked out Monmouth Battlefield State Park, a Revolutionary War site where, my brother reminded me, my parents used to picnic. No luck. Then I drove to Freehold Raceway Mall where he’d walk daily before the pandemic, and I checked cars in the parking lot. Nothing.

The man was good and lost, orbiting well outside known patterns, beyond anywhere that logic would suggest he’d go.

Nine hours in, my father was found by cops in Union City, New Jersey, 50 miles north, after he sideswiped two parked cars. No one was injured. I thanked the Freehold officers who coordinated his return. A sergeant said simply, “We all got fathers, Al.”

My brother brought our dad home, where I asked him, “What the hell?”

“My back,” he said, referring to the arthritis he endures from piling tons of bricks and blocks into walls during a lifetime of labor. “It got to be too much.”

It makes sense, said Kellie Butsack, an associate director at the Alzheimer’s Association Delaware Valley chapter. “In a brain affected by dementia, people can’t cope like they used to. The back pain made him get in the car.”

But why Union City? When Andrea and I retrieved the Honda two days later, I got a clue. The place is on a cliff over the Hudson River, across from Manhattan’s spiky towers.

People with dementia lose recent memories and wind up thinking more about their younger days, Butsack said. Past becomes more present.

“They want to go back to where they grew up,” she said. “I’d guess your father was headed to New York City, maybe for one last singing audition, or to see family.”

Is there something in the man’s head that propelled him toward his life’s unfinished work? Do we really move closer to our beginnings when we near our end?

“It was my last hurrah,” my father said cryptically, unwilling or unable to explain further, or to say where he was during nine hours of a journey that should have taken just 60 minutes.

He remembered the accident, though, and his tough-guy chiding of the owner of one of the cars he hit.

“He was parked wrong,” my dad recalled, deflecting blame. He said that after the accident, the owner scurried from his apartment to assess the damage. “So I told him, ‘Were you just sittin’ by your window, waitin’ for your car to be hit? How’d you get down here so fast?’”

I fretted about what I had to do next.

The hardest conversation to have with aging parents is telling them to stop driving and hand over their car keys — more difficult than talking to parents about their final wishes or wills, according to a survey by Pfizer, the pharmaceutical company, and Generations United, a Washington, D.C., nonprofit advocacy group focused on intergenerational issues.

When you’re trying to figure out how to do it, “manipulation and deception are justified if it’s going to save people’s lives,” according to Gary Kennedy, director of Montefiore Medical Center’s Division of Geriatric Psychiatry in New York City.

You’re within your rights, experts say, to disable the vehicle, move it, sell it, or just hide the keys. Some call their local departments of motor vehicles to big-foot seniors out of their licenses.

In cowardly fashion, I told my dad that “the authorities” took his keys because they feared he’d kill someone, or die in a wreck. I put the car in his garage.

Dementia doesn’t make a smart guy stupid, and my father saw through it.

“You killed me!” he raged. “I’m dead now, stuck in a house. I might as well just die. You didn’t fight for me.”

I told him that cabs, or his caretakers, or I could drive him anywhere. But he saw all of it slipping away — control, liberty, the ability to live on his own terms. He yelled, “I fought for this country, raised a family. I did the right thing.”

A couple of days later, my dad went missing again for two hours, this time on foot, walking a mile to his bank. A woman picked him up along the side of the road and drove him home.

“Pop, you can’t keep doing this,” I snapped. He accused me of not caring about him, and ordered me out of his house.

Despite his edict, I’d like to bring him a birthday present this week.

Butsack of the Alzheimer’s group urged me to “see the humor in the disease: People can’t hold grudges long because they don’t remember they’re angry. Go see your dad.”

I said I will.

A cousin who feared I’d cave warned me not to give the keys back.

I said I won’t.

But there’ll be a changed and charged atmosphere in the house as I sit with my old man — he with his loss and his misfiring brain cells, me with my sin, in the quiet living room near the photos of my mom, her eyes on us both.