From the moment the World Trade Center towers came crashing down on that tragically historic Tuesday, they have been hailed as true national heroes.

I’m speaking of the New York City firefighters, of course, that tough, valiant fraternity in turn-out gear that has had the unimaginable job of poring through mountains of smoking wreckage in a gruesome, dangerous search for life. To an anxious nation that could do little but look on helplessly and pray, they are our heroes, all of them.

But the firefighters have no use for the hero worship that’s been heaped on them by everyone from Mayor Rudolph Giuliani to President George Bush to the friends who congratulate them when they get home to their neighborhoods after another grueling day.

That’s what my uncle, Tom Flynn, told me recently. And my uncle should know. Of his six sons, five have clawed day and night through the rubble known as Ground Zero. Four of them – Tom, Michael, Stephen and Joseph – are New York City firefighters. The other, John, is a burly ironworker who now does the kind of perilous construction work high over Manhattan that his father had done for 42 years before him.

“There’s no one talking about heroism in those firehouses, I can tell you that,” my uncle said when I called him in Staten Island to ask about the redheaded Irish cousins I grew up with in Brooklyn – my family’s reluctant heroes. “Tom says he can’t walk down the street without someone coming up to pat him on the back. Maybe it’s because we’re all looking for heroes these days, you know? Football heroes, rock star heroes, and not a hero in the bunch. But the firemen feel they’re just doing what they’ve always done, which is to try to rescue people. In this case, it’s just a lot tougher. Firemen are such a close-knit group, like a family, really, and when they were digging through the rubble they were looking for their friends.”

On the morning of Sept. 11, Joseph’s company was the second from Brooklyn to respond to what they thought was a fire on the 80th floor of one of the towers.

“By the time Joe’s company got there, ” my uncle recalled, “all they saw were the pieces of the engine from the first company – from Red Hook – sticking out of the rubble. I think there were 12 of them buried in there. Joe and the guys just started digging with their hands, digging holes. They lowered one guy down 60 or 70 feet and he was in shock when they pulled him up. There were so many body parts in there. Joe stopped by to visit the next morning, and he just sat there very quietly. He didn’t say much.”

Soon, Tom’s company had joined all the others at the scene. John was working that morning on a building uptown, on 57th Street, when he heard about the devastation in lower Manhattan. He and another ironworker jumped on a truck and made their way downtown. By then, there were dazed firemen sitting on the curbs, their heads in their hands. John scrambled up onto the rubble and started digging into the debris with his hands. Stephen, who was a New York cop before joining his brothers in the fire department, had been on disability for a bad knee the last three years. On Wednesday morning, however, he ran down to his basement and dug out his helmet and other gear and went to the site to work. Michael, who retired from the fire department last year, also rushed in to help search for bodies.

The sons asked their father if he wanted to go, too. He did, of course. My uncle had spent his working life adding tall buildings to the New York City skyline. For nearly three years as an ironworker on the Verrazano-Narrows Bridge, at the mouth of New York harbor, he had begun each day by ascending towers that soared 700

feet into the air.

He had helped to erect some fine structures in his life – bridges and buildings meant to last. And now the terrorists had proved how easily it could all be undone, how even the most magnificient buildings could be erased from the skyline in a terrifying instant. My uncle felt he had to see that, too.

With Stephen and Michael, he traveled to the site by ferry in the rain. He told the cops at the barricade that he was an ironworker and wanted to help. The cops thanked him but wouldn’t let him pass. Stephen tossed his car keys across the line to his father and the two sons soon disappeared into the crowd of rescue workers.

“I just drove home and watched it on TV, like everybody else,” my uncle said. “I felt helpless that I couldn’t be over there doing something. The firefighters were working 24-hour shifts – 12 at the scene and 12 at the firehouse. But in the first days they were staying all night, digging for live bodies. They wouldn’t leave until they found their friends. They just kept hoping and hoping they would find people alive in there. Guys were just laying on the sidewalks to rest. After a while they were like zombies from lack of sleep. There were so many body parts, pieces everywhere. After a while there was the stench, too, and the possibility that something would collapse on them. But they never stopped, as long as there was a chance.”

Two weeks later, when that chance had become too slim to even measure anymore, they tore down the remaining seven stories of the south tower. The rescue part of the operation was finally over. More than 6,340 people are still missing, including some 300 firefighters. Now all that’s left is the grisly cleanup and the sifting for remains that might eventually put names to the dead.

And for the firefighters, of course, there are all the painful funerals that have kept their neighborhood churches filled in every borough of the city.

“There’s a lot of sadness everywhere, and that won’t go away for a long time,” my uncle said. “Yeah, the firefighters are an amazing breed who do a dangerous job. I’ve known a lot of them, and they’re mostly good family men, and tough guys in a nice, quiet kind of way. But they’d never call themselves heroes. They’d just say they were doing their jobs as best as they could.”