Across the nation, Americans are marking the 25th anniversary of 9/11, remembering the shock, those who died, and the wide-ranging consequences of al-Qaida's attacks on symbols of U.S. power and prosperity.
Friday's milestone will feature traditional memorial ceremonies—including wreath-laying, flying flags, silent moments, vigils, the reading of victims' names, and volunteer efforts—honoring a day that roughly half of U.S. adults consider the most historic moment of their lifetime, according to a recent poll.
For others, the date serves as a period for private reflection or classroom lessons about the single morning that claimed nearly 3,000 lives and led to decades of aftermath, ranging from personal sorrow to overseas wars.
Police Officer Casey Kloepfer plans to spend Friday at the Brooklyn precinct where his father, Officer Ronald Kloepfer, reported for duty that morning before being dispatched to the World Trade Center, from which he never returned.
Though Casey Kloepfer was only 4 years old at the time, he grew up hearing about his father's passion for helping others through police work, leading him to become an officer this past June.
"It’s big footsteps to fill, but it’s definitely something that I take very seriously and want to continue to honor him and be the best police officer I can," the 29-year-old said by phone this week. He wears his father's badge number and has joined the New York Police Department lacrosse team, which his dad founded.
Unlike his predecessors, Trump will not be at the Ground Zero memorial
On Sept. 11, 2001, al-Qaida extremists hijacked four commercial jets and crashed them into New York's World Trade Center, the Pentagon and a field near Shanksville, Pennsylvania.
The impacts brought down the World Trade Center's twin towers — icons of U.S. economic power, and among the tallest buildings on Earth — and blew a hole in the Pentagon, the U.S. military's fortress-like headquarters near Washington.
The fourth plane also was headed for the nation's capital, officials concluded, but the aircraft went down in Pennsylvania after passengers and crew members stormed the cockpit and fought the hijackers.
“In the course of history, there are a few moments that divide time into, really, what came before and after,” President Donald Trump said at a 9/11 remembrance in Washington this week. The Republican, who was in his native New York on Sept. 11 and has often recounted his memories, plans to attend the Pentagon's anniversary ceremony Friday.
Vice President JD Vance is expected at the observance at the National Sept. 11 Memorial in New York, while other administration officials are headed to the Flight 93 National Memorial in Pennsylvania.
Planned remembrances extend far beyond the attack sites, from beams of light projecting from New Hampshire's Mount Washington to a stair climb at Mississippi State University's football stadium to a ceremony at Honolulu's 9/11 memorial.
At this year’s ceremony, there will be a poignant tribute to those who died from health issues in the wake of the attack
Political speeches are traditionally absent from the New York memorial, where relatives read the names of all victims, punctuated by silences marking key moments in the timeline.
This year, the ceremony adds a new silent tribute for those exposed to the toxic dust from the twin towers' collapse who later died of cancer and other illnesses. Uncertainty remains over how many people developed health issues tied to the debris.
The addition underscores how the lingering shadow of the strikes continues to reach far across the U.S. and beyond.
The U.S.-led global campaign against terror brought invasions of Iraq and Afghanistan—Washington’s longest war—alongside the detention and harsh interrogation of suspects within secret CIA prisons worldwide.
Although American forces killed al-Qaida leader Osama bin Laden in Pakistan in 2011, accused 9/11 architect Khalid Sheikh Mohammed remains without a trial 23 years after his capture.
The event permanently altered U.S. aviation, expanded federal surveillance, intelligence powers, and banking rules, while sparking ongoing debate over security versus freedom. The Department of Homeland Security, numerous state-level anti-terror laws, and massive counterterrorism spending are all post-9/11 developments.
So is the widespread public vigilance captured by the motto " if you see something, say something."
Right-wing figures have spent the lead-up to the event smearing New York City’s first Muslim mayor
The Sept. 11 attacks generated a wave of patriotism that prompted many Americans to join the military, police forces, fire departments, or other public agencies. Yet alongside the national unity remembered by many, the events also sparked mistrust, prejudice, and hate crimes directed at Muslims.
In the quarter-century since, Muslim Americans have taken on an expanding role in civic life from statehouses to Congress to New York City Hall, where Zohran Mamdani is the city's first Muslim mayor.
Nevertheless, he is facing criticism for planning to participate in the anniversary ceremony at Ground Zero, an event his predecessors have attended for years.
Some complaints came from Republican ex-Gov. George Pataki and relatives of 9/11 victims, who pointed in part to past remarks made about the attacks by some of Mamdani's political associates. Former Mayor Rudy Giuliani, a Republican, also spoke out against Mamdani attending.
Mamdani, a Democrat, responded this week that he loves the city and country and wants the commemoration to focus on victims' families, emergency workers, and New Yorkers who aided one another after what he termed a "horrific act of terror." The 34-year-old mayor was an elementary school student in New York on 9/11.
Although Sept. 11 is not a federal holiday, Congress has designated the date as both Patriot Day and a National Day of Service and Remembrance.
"One appropriate way to remember is by serving," says Jay Winuk, who lost his brother Glenn Winuk and subsequently co-founded the volunteer group 9/11 Day alongside his friend David Paine.
The organization connects individuals with meal-packing projects and other volunteer opportunities. This year, the group arranged for dozens of Times Square billboards to pause their advertising at 9: 11 a.m. Friday.
Instead, the screens will simply display the time.
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