There are countless stories of heroism from September 11, 2001, but one has always represented something particularly American to me.

Flight 93.

The passengers and crew aboard United Airlines Flight 93 did not begin that morning as soldiers.

They were ordinary people taking an ordinary flight.

Then they learned that their airplane had been hijacked.

Through telephone conversations with people on the ground, passengers discovered that airplanes had already struck the World Trade Center. They realized something terrifying: they weren’t merely hostages.

Their airplane was a weapon.

And then something remarkable happened — they acted.

We will never know precisely what would have happened had those passengers not fought back. We do know that the hijackers crashed Flight 93 into a Pennsylvania field rather than reaching their intended target in Washington.

Forty passengers and crew members were killed.

Their actions are remembered today because they illustrate one of the most important lessons of September 11: free people are not helpless.

That lesson remains relevant 25 years later.

America faces different threats today. International terrorism has not disappeared. We confront hostile foreign governments, cyberattacks, disinformation, political violence and challenges from adversaries who understand that American power rests on more than aircraft carriers and nuclear weapons.

It rests on Americans themselves.

Our country’s greatest strength has never been Washington.

It is the willingness of ordinary citizens to take responsibility when responsibility suddenly lands in their laps.

That is what happened aboard Flight 93.

There was no committee hearing. There was no government program. There wasn’t time to wait for someone else to solve the problem.

Ordinary Americans gathered the information available to them, understood the danger, made a decision and acted.

There is something deeply American about that.

Our country was founded on the radical idea that citizens are capable of governing themselves.

The Founders did not envision Americans as passive subjects waiting for government to direct every aspect of their lives. They believed free people could build communities, create institutions, solve problems and defend their liberty.

That tradition runs through our history.

It was present in the citizen soldiers at Lexington and Concord.

It was present in generations of immigrants who arrived with little more than ambition and built lives, families and businesses.

It was present in Americans who volunteered to defend this country in wars around the world.

And it was present aboard Flight 93.

There is another lesson here.

Courage does not mean the absence of fear.

Those passengers must have been terrified.

Courage is understanding the danger and acting anyway.

We understandably commemorate September 11 by remembering the nearly 3,000 people murdered that morning. We should.

But our remembrance should also teach our children about agency, citizenship and courage.

A generation is growing up for whom 9/11 belongs to history in the same way Pearl Harbor belonged to history for many of us.

That makes our responsibility greater, not smaller.

Tell them about the firefighters who ran toward burning buildings.

Tell them about police officers who refused to abandon people trapped inside.

Tell them about the military personnel and civilians who helped one another at the Pentagon.

And tell them about a group of passengers flying over Pennsylvania who realized that nobody was coming to save them.

So they tried to save others.

Our politics today often teaches Americans to think of themselves as victims of forces beyond their control. Government is responsible. Corporations are responsible. The other political party is responsible. Somebody else must fix it.

Flight 93 teaches the opposite lesson.

Sometimes history hands responsibility to you.

Sometimes there is no perfect option.

Sometimes nobody else is coming.

And sometimes ordinary citizens must stand up and say: We will do something.

Twenty-five years after September 11, that may be one of the most important lessons America can remember.

Saul Anuzis is the president of the 60 Plus American Association of Senior Citizens and a Republican Party politician from the U.S. State of Michigan. He was chairman of the Michigan Republican Party from 2005–2009 and was also a candidate for national chairman of the Republican National Committee in 2009 and 2011, as well as a Member of the RNC from 2005–2012.