It’ll stay with me forever.

I was preparing for a busy morning serving as an assistant chief in Prince George County, Maryland. Then came the worst attack on U.S. soil. I, like so many Americans, watched in horror at the scenes from the World Trade Center, the Pentagon, and Shanksville, Pennsylvania, unfolded.

Firefighters across 211 FDNY firehouses also went to work that morning of September 11, 2001. Nearly 350 of them, from 61 firehouses, never came home. Amid the smoke, flames, and falling debris at the World Trade Center, our brothers and sisters bravely ran toward danger, saving countless lives at the Twin Towers.

Their sacrifices inspired my immediate travel to New York City as one of 400-plus volunteers mobilized by FEMA and the National Fallen Firefighters Foundation. The work was difficult and around the clock, operating out of a makeshift field office providing resources to the families and coworkers of the city’s missing and fallen firefighters, and to the workers involved in rescue and recovery at Ground Zero.

In New York, I saw the best of humanity in the worst of times. I remember after a long day a group of colleagues and I stopped to eat at a local restaurant in Manhattan, near where many response organizations had set up. When we went to pay, we found out somebody had already taken care of the bill. Whoever it was knew why we were there. But it was the least we could do to fulfill the nation’s pledge, in its earliest days, to never forget.

That same promise is being tested 25 years later.

There’s not a schoolchild today with memories of 9/11. A growing number of their teachers weren’t born yet, either. That’s why this year brings a renewal of our responsibility.

“Never forget” is a promise we must work to keep.

To never forget means teaching our children, in an age-appropriate way, about 9/11. For younger kids, it’s emphasizing what it means to remember, respond in an emergency, serve a community, and provide extraordinary compassion. For older ones, it’s the human stories of the civilians who were killed, the families forever changed, and the first responders who put it all on the line.

We need more efforts from groups like OOPA’s World of Words that are working to bridge this gap for modern-day students and teachers alike, ensuring the stories of 9/11 are properly understood by American children for years to come.

To never forget means educating ourselves on the from 9/11, and advocating for the responders — suffering from related cancers, respiratory diseases and other health conditions — who provided rescue and recovery.

More than 95,000 responders are now enrolled in the WTC Health Program, according to the most recent data. The program, funded through 2040, provides medical monitoring and treatment. These responders, firefighters among them, deserve the peace of mind that comes with full, permanent funding.

To never forget means supporting the families of those who have died in the years since from 9/11-related illnesses. They should not have to face unnecessary red tape to receive the benefits and recognition their loved ones earned.

Firefighters who succumbed to illness are heroes of 9/11, too. Tragically, 343 of them — matching the official number of FDNY members who died that day — are honored on the National Fallen Firefighters Memorial, their deaths now considered line of duty. They come from New York, New Jersey, and faraway states including Indiana, Missouri, Utah and Washington. Continued attention on research linking post-9/11 exposure and cancers will expand this number further, bringing closure to many more families across the country.

To never forget means turning remembrance into action. Across the country, 9/11 Memorial Stair Climbs have helped firefighters and community members honor our Fire Heroes by climbing the equivalent of the 110 stories of the World Trade Center.

I have heard younger firefighters say they would not have known what happened on 9/11 if not for these climbs and new initiatives such as #ForThe343. Crucially, local stair climbs also raise money for nonprofits that continue serving the families of 9/11 fallen firefighters with college scholarships, counseling programs, and help navigating benefits programs.

Lastly, to never forget means applying what we’ve learned in the fire service. In the years since, research and experience have deepened our understanding of occupational cancer, behavioral health, peer support, and the long-term risks firefighters face every day.

The work has brought about larger changes, and even legislation such as the Honoring Our Fallen Heroes Act, which recently added 20 service-related cancers to the federal Public Safety Officers’ Benefits Program. It’s on us to keep learning and adapting, deepening the legacies of our 9/11 heroes in the process.

In 2001 we promised to remember those who made the ultimate sacrifice. We promised to support their spouses and children. We promised that firefighters affected by 9/11 would receive the care they need.

This year, as the nation marks another year since 9/11, let’s keep the promises we made a quarter-century ago.

We owe it to the fallen, the sick, their families, and the next generation: the passage of time won’t dull our commitment.

We’ll never forget. 

Victor Stagnaro is a 40-year veteran of the fire service. He now serves as chief executive officer of the National Fallen Firefighters Foundation, a Congressionally established nonprofit that honors America’s fallen fire heroes, supports their families, and works to reduce preventable firefighter death and injury.