New York: Americans remembered 9/11 on Sunday with reading the names of victims, volunteering and other tributes on the 21st anniversary of the September 11, 2001 terrorist attacks on the World Trade Center in the United States.

A tolling bell and a moment of silence began the commemoration at ground zero in New York, where the World Trade Center’s twin towers were destroyed by the hijacked-plane attacks of Sept. 11.

Firefighter Jimmy Riches’ namesake nephew wasn’t born yet when his uncle died, but the boy took the podium to pay tribute to him.

“You’re always in my heart. And I know you are watching over me,” he said after reading a portion of the nearly 3,000 victims’ names.

Victims’ relatives and dignitaries also convened at the two other attack sites, the Pentagon and a field in Pennsylvania.

Other communities around the country are marking the day with candlelight vigils, interfaith services and other commemorations. Some Americans are joining in volunteer projects on a day that is federally recognized as both Patriot Day and a National Day of Service and Remembrance.

More than two decades later, Sept. 11 remains a point for reflection on the attack that reconfigured national security policy and spurred a U.S. “war on terror” worldwide.

Sunday’s observances, which follow a fraught milestone anniversary last year, come little more than a month after a U.S. drone strike killed a key al-Qaida figure who helped plot the 9/11 attacks, Ayman al-Zawahri.

It also stirred — for a time — a sense of national pride and unity for many, while subjecting Muslim Americans to years of suspicion and bigotry and engendering debate over the balance between safety and civil liberties. In ways both subtle and plain, the aftermath of 9/11 ripples through American politics and public life to this day.

And the attacks have cast a long shadow into the personal lives of thousands of people who survived, responded or lost loved ones, friends and colleagues.

More than 70 of Sekou Siby’s co-workers perished at Windows on the World, the restaurant atop the trade center’s north tower. Siby had been scheduled to work that morning until another cook asked him to switch shifts.

Siby never took a restaurant job again; it would have brought back too many memories. The Ivorian immigrant wrestled with how to comprehend such horror in a country where he’d come looking for a better life.

He found it difficult to form the type of close, family-like friendships he and his Windows on the World co-workers had shared. It was too painful, he had learned, to become attached to people when “you have no control over what’s going to happen to them next.”

“Every 9/11 is a reminder of what I lost that I can never recover,” says Siby, who is now president and CEO of ROC United. The restaurant workers’ advocacy group evolved from a relief center for Windows on the World workers who lost their jobs when the twin towers fell.

On Sunday, President Joe Biden plans to speak and lay a wreath at the Pentagon, while first lady Jill Biden is scheduled to speak in Shanksville, Pennsylvania, where one of the hijacked planes went down after passengers and crew members tried to storm the cockpit as the hijackers headed for Washington. Al-Qaida conspirators had seized control of the jets to use them as passenger-filled missiles.

Vice President Kamala Harris and husband Doug Emhoff joined the observance at the National Sept. 11 Memorial in New York, but by tradition, no political figures speak at the ground zero ceremony. It centers instead on victims’ relatives reading aloud the names of the dead.

Readers often add personal remarks that form an alloy of American sentiments about Sept. 11 — grief, anger, toughness, appreciation for first responders and the military, appeals to patriotism, hopes for peace, occasional political barbs, and a poignant accounting of the graduations, weddings, births and daily lives that victims have missed.

Some relatives also lament that a nation which came together — to some extent — after the attacks has since splintered apart. So much so that federal law enforcement and intelligence agencies, which were reshaped to focus on international terrorism after 9/11, now see the threat of domestic violent extremism as equally urgent.

-APN