Former President Joe Biden marked the 25th anniversary of the September 11 terrorist attacks on Friday with a post on X honoring the nearly 3,000 people killed and the first responders who rushed into the World Trade Center and the Pentagon, framing national unity as the enduring lesson of the attacks even as he continues treatment for advanced prostate cancer.
“Twenty-five years ago today, we lost 2,977 souls and in the years since, thousands more to illnesses caused by the attack on our country,” Biden wrote. “This morning, Jill and I hold close the families who carry that loss every day. We honor the heroes of September 11th: the firefighters and police officers who rushed into the towers and the Pentagon, the passengers who fought back over Shanksville, and the generation that stepped up to serve in the aftermath. Even now, we remember the greatest lesson of one of our nation’s darkest days: at our most vulnerable, unity is our most powerful strength. We will never forget.”
The post, published at 10:34 a.m. on September 11, 2026, came as Biden attended the annual commemoration ceremony at the National September 11 Memorial & Museum in lower Manhattan, where he was joined by three other living former presidents — Barack Obama, George W. Bush and Bill Clinton — along with their spouses, Michelle Obama, Laura Bush and Hillary Clinton.
A Somber Reunion at Ground Zero
The gathering marked a rare joint appearance by four former presidents at the site where the World Trade Center’s Twin Towers once stood. Vice President JD Vance also attended the New York ceremony, while President Donald Trump traveled instead to the Pentagon, where he delivered remarks marking the attack that killed 184 people at the building on September 11, 2001.
Also present in Manhattan were Senate Minority Leader Chuck Schumer, New York City Mayor Zohran Mamdani, and former New York City mayors Bill de Blasio, Rudy Giuliani and Michael Bloomberg. Before the ceremony began, Mamdani shook hands with Giuliani, who had previously called on the city’s first Muslim mayor not to attend the event.
The ceremony followed the tradition of pausing for moments of silence at the precise times each of the four hijacked planes struck their targets or crashed, along with the times each tower fell. Bells tolled at 8:46 a.m. and 9:03 a.m. to mark the strikes on the North and South Towers, at 9:37 a.m. to mark the attack on the Pentagon, and again at 9:59 a.m. and 10:28 a.m. to mark the towers’ collapse. The reading of victims’ names by family members continued throughout the ceremony, a tradition observed at the site every year since the attacks.
Biden Attends Mass Ahead of Anniversary Despite Cancer Battle
Biden’s tribute followed his attendance the previous evening at a 9/11 memorial Mass at St. Patrick’s Cathedral, celebrated by Archbishop Ronald Hicks. Biden’s arrival was unannounced and drew applause from a congregation that included victims’ families. Despite being in the midst of treatment for stage four prostate cancer, Biden stayed for nearly an hour after the service to speak individually with bereaved family members and first responders, according to accounts from attendees. Mamdani and New York Governor Kathy Hochul also attended the Mass.
Biden’s office disclosed in May 2025 that he had been diagnosed with an aggressive, hormone-sensitive form of prostate cancer that had already metastasized to his bones by the time it was discovered, with a Gleason score of 9 out of 10. He completed a course of radiation therapy in October 2025. Just three days before the 9/11 anniversary, on September 8, Biden posted a lengthy statement marking Prostate Cancer Awareness Month, writing that the treatment “worked as intended” and that he remained active, including finishing work on his forthcoming memoir. He used the occasion to urge American men to talk with their doctors about screening, noting that more than 330,000 men are expected to be diagnosed with prostate cancer in 2026.
A Message Consistent With Past Anniversaries
Friday’s statement echoed themes Biden has struck on previous 9/11 anniversaries throughout his presidency and since leaving office. Marking the 21st anniversary in 2022 during a ceremony at the Pentagon, Biden said he hoped Americans would remember that in the aftermath of the attacks, “we dug deep. We cared for each other. And we came together,” and described the day as being “not about the past” but about the nation’s ongoing “obligation, a duty, a responsibility to defend, preserve and protect our democracy.”
A year later, marking the 22nd anniversary while traveling back from a trip to India and Vietnam, Biden called on Americans to unite despite political divisions, telling those gathered at a military base in Alaska to “honor September 11 by renewing our faith in one another.” The message of unity amid national division has remained a consistent thread in Biden’s public remarks on the anniversary in the years since he left the White House in January 2025.
Trump Marks Anniversary With Formal Proclamation
Biden’s post came the same day President Trump issued a formal proclamation designating September 11, 2026, as Patriot Day, calling on federal departments and agencies to fly the American flag at half-staff in honor of the 2,977 victims of the 2001 attacks and inviting governors, organizations and individuals nationwide to join the observance. Trump signed the proclamation on September 9, two days ahead of the anniversary.
Unlike the other living former presidents, Trump did not attend the Manhattan ceremony, instead traveling to the Pentagon with first lady Melania Trump. Reports ahead of the anniversary indicated Trump had opted against attending the New York event after the National September 11 Memorial and Museum, which has barred political speeches at its ceremony since 2012, declined to grant him a speaking slot — a characterization the White House has disputed. A White House spokesperson said Trump had separately honored 9/11 first responders and New York Fire Department officials at the White House on September 8, ahead of the anniversary.
Background on the Attacks
The September 11, 2001 attacks remain the deadliest terrorist strike in American history. Nineteen al-Qaeda hijackers commandeered four commercial airliners, crashing two into the World Trade Center’s Twin Towers in Lower Manhattan and a third into the Pentagon in Arlington, Virginia. Passengers aboard the fourth plane, United Airlines Flight 93, stormed the cockpit after learning of the other attacks, and the aircraft crashed into a field near Shanksville, Pennsylvania, before it could reach its intended target in Washington. In total, 2,977 people were killed, not including the 19 hijackers.
In the 25 years since, thousands of additional deaths have been attributed to illnesses linked to toxic exposure at the attack sites, particularly among first responders and recovery workers who spent weeks and months at Ground Zero. Mamdani’s office released documents this week related to air quality readings following the attacks, which showed the air around the fallen towers remained toxic for significantly longer than officials had publicly acknowledged at the time.
Broader Commemorations Across the Country
Beyond New York and the Pentagon, ceremonies were also held Friday in Shanksville, Pennsylvania, at the Flight 93 National Memorial, where the passengers and crew who died fighting back against hijackers are honored annually. Across the country, government buildings, schools and private organizations held moments of silence and remembrance events throughout the day, consistent with the observance of Patriot Day, which has been marked in some form every September 11 since it was first designated in 2002.
Biden’s Friday statement did not reference any policy positions or current political disputes, focusing instead on remembrance of the victims, tribute to first responders and members of the “generation that stepped up to serve” in the military and public service fields in the years following the attacks. The message closed with the phrase “We will never forget” — the same formulation that has anchored public commemorations of the anniversary across administrations of both parties for a quarter century.