On December 7, 1941, my grandmother’s father, like so many other Navy men stationed at Pearl Harbor, assumed all the gunfire down at the base was a drill.

It was a Sunday, and he was sleeping in on a day off from his duties as an officer aboard the USS Nevada. His daughter told him around 7:30 a.m. that the family had not received their newspaper. She asked if she could borrow the one next door to read the funny pages.

Worried that she might actually steal a neighbor’s newspaper, he rolled out of bed to keep an eye on her. He went to the kitchen and started making coffee. His wife tried calling the newspaper printing plant to see why the family’s copy had not been delivered. She called again and again, but could not get through.

When she finally did, she was interrupted by a loud burst of gunfire outside. The family cursed the Army for running a surprise military exercise on a Sunday morning. But soon, my grandmother and her parents realized this one was different. The armed forces often ran drills, but these explosions were too loud, too intense.

My great-grandfather called up his brother, another naval officer, who lived in a house overlooking the base, to see just what the hell was going on.

His brother glanced out his window and said that it looked like a mock battle between the battleships and army airmen, until — my god — a shell whistled over his house and exploded in midair outside. He had to hang up. Something was wrong at Pearl.

My grandmother, her family, and many of their neighbors went outside to survey the sky. It still seemed like a drill, but there were too many planes. And the explosions were too close to civilian structures. “Those damned fools,” my grandmother’s father thought as he stared upward.

He checked his radio for news and got some Army jargon: “Attention please! Attention please! It has just been announced that Oahu is under enemy attack. There is no need to be alarmed. All persons please stay off the streets and do not use the telephone. All police officers and firemen report to your stations at once.”

Soon the reports became more specific, identifying the enemy as Japanese and instructing all Army and Navy personnel to report to their stations. So my grandmother’s father threw on a Hawaiian shirt, said goodbye to his family, and ran out to his car.

“I wasn’t very sure when I would see them again,” he later wrote in his diary.

His fear was justified: as he drove toward drove toward the base with several other officers in uniform, gunfire lit up the road behind them. He swerved into a ditch to avoid being strafed. Overhead, a Japanese Zero screamed by him and the other passengers.

“With a roar, we saw the Rising Sun go past — just to the left of the road, at about treetop height,” he later wrote. “He was so close, we could see the expression on the pilot’s face. One look convinced me.”

Pearl Harbor was under attack.

As he reached the base itself, he witnessed the dire state of affairs: billowing black clouds from oil fires shielded almost the entire harbor from view. Officers were running all over the place, trying their best to defend the base.

My grandmother’s father was nearly paralyzed with anger:

There will probably never be another moment like that in my life. The sight I beheld so stunned me that I was unable to move, unable to talk, even unable to think. I could only stare in first amazement, then disbelief, and finally in rage. The tears coursed down my face as uncontrolled as rain. There before me lay the backbone of the greatest navy in the world — broken, twisted wrecks in a blazing sea of oil.

His ship, the Nevada, had been torpedoed, and its crew had been forced to beach it on a coral ledge. With no post to defend, my grandmother’s father found a company of Marines manning anti-aircraft guns. They stationed him behind a turret, and until 11:30 a.m. — around when the attack started to subside — he scanned the sky for enemy planes.

When the attack ended, someone brought him a uniform so he wouldn’t have to walk around the base looking like he had just wandered off of the golf course. He stayed at the base the rest of the day, cleaning up and helping the wounded.

All of this happened over 75 years ago, and I only know these eyewitness details because my grandmother recently transcribed her father’s diary. She remembers the day, of course, but only as a child would. When I asked her about it recently, she joked that she no longer knows if her recollections are her own or just constructed memories of so many other stories about Pearl Harbor.

Hers is the last generation that has any memory of the day that President Franklin Delano Roosevelt predicted “will live in infamy.” He was right — but only for a time.

That time is drawing to a close, and may even be already over. Pearl Harbor is not yet a mere textbook anecdote, like Benedict Arnold’s betrayal or even Abraham Lincoln’s assassination. But wait another generation, and December 7 — and all of World War II, for that matter — won’t command the same gravity it has held for nearly a century.

It always happens this way. Despite the cries to remember the Alamo, to remember the Maine, and, yes, even to never forget the attacks of September 11, 2001, the immediacy of tragedy always passes. Fact becomes myth, myth legend, and legend eventually falls into obscurity.

I hope stories like the ones told by my grandmother and her father prevent Pearl Harbor from slipping away.