It’s been two decades since the day that changed America forever.

On Sept. 11, 2001, nearly 3,000 people died after Islamic extremists tied to Al Qaeda hijacked four jetliners and used them as missiles.

NBC 4’s Colleen Marshall and photographer Charles Busby went to New York City 20 years ago to cover the attack on the World Trade Center and the aftermath.

To mark the 20th anniversary, they went back to New York and all this week will share the stories of 9/11 – 20 years later.

COLUMBUS (WCMH) – Nearly 3,000 people died in the terror attacks of September 11, 2001, with more than 2,600 killed at the World Trade Center.

Every one of those victims left someone behind.

A memorial fountain sits on the footprint of the former South Tower with nearly 3,000 individual strands of water, representing the lives lost at Shanksville, in Washington, and here at the World Trade Center.

One of those strands represents Joe Giaconne.

“At 8:46 in the morning, my brother Joe vanished,” said Jim Giaconne.

Jim Giaconne was on a construction site when he heard about an accident at the World Trade Center. He worked his way to the roof.

“And I thought I was going to get a wisp of smoke because, in my mind’s eye, I thought that maybe a single-engine plane or a commuter helicopter had mechanical difficulties, but when I go to that vantage point, I could see that the whole top of the tower was engulfed in flame and smoke,” he said.

His brother Joe worked on the 103rd floor of the North Tower.

“Even when the towers went down, you know, we still held on to hope that he had somehow found a way out, that staircases were still open, elevators were still operational, just hoping against hope,” Giaconne said.

Joe Giaconne’s story is similar to that of John Castro.

“About 8:30, 8:45, right after that first plane hit and she said she was OK, we haven’t heard anything since,” Castro said 20 years ago.

On Sept. 13, 2001, he was searching for his son’s fiancé.

“We love her and she was going to be part of our family,” Castro said.

The Castros joined thousands of others, wandering from hospital to hospital in a futile search for the missing.

But Jim Giaconne said he went one step further back then, personally going to Ground Zero.

“After a few days, I got in dressed as a firefighter,” he said.

With the help of his firefighter best friend…

“And I put on his bunker gear and we drove down dressed as firefighters, and we were waved right through all the checkpoints,” he said. “It was a war zone down here.”

It was when he reached Ground Zero that Jim finally buried hope.

“As soon as I came down, I knew that there was nobody coming out,” he said. “It was too complete. It was just pulverized concrete and steel and fire and smoke and I call my dad and I told him Joe wasn’t coming home.”

Today, Jim volunteers at the Family Tribute Museum and tell strangers about Joe and the life he is missing.

“His daughter was just married two years ago,” Jim said.

“The events of September 11 have changed me in ways good and bad, big and small,” he added. “I can honestly say now I am a much, much more tolerant person. I am a much more accepting person. I fear extremism in anything, in religion and politics. Anything extreme can go wrong, so I don’t blame one religion or another.”

Jim said he knows what his brother would think of the memorial museum and Jim’s role there today.

“I think he would be proud,” he said. “I think he would appreciate it. I think he would have done the same thing for me.”

Joe Giaconne was one of 658 people who reported for work that day at Canter Fitzgerald in the North Tower. None of them survived.

Jim Giaconne now helps lead tours through the World Trade Center neighborhood as a volunteer at the Family Tribute Museum, which is struggling financially due to the COVID-19 pandemic lockdown.

For more information on how you can help, click here.