Updated September 11, 2021 at 9:00 AM ET
Twenty years to the day a pair of hijacked airliners destroyed the World Trade Center towers, another plane punched a gaping hole in the Pentagon and a fourth passenger jet crashed in a Pennsylvania field after passengers sought to regain control from hijackers, Americans across the country reflected on the events that forever changed their country.
Nearly 3,000 people were killed on Sept. 11, 2001, which not only sparked enormously costly and largely unwinnable wars in both Afghanistan and Iraq, but also spawned a domestic war on terrorism, rewriting the rules on security and surveillance in the U.S., the repercussions of which continue to reverberate.
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People were gathering in lower Manhattan. President Biden, first lady Jill Biden, former President Barack Obama and Michele Obama and former President Bill Clinton and former Secretary of State Hillary Clinton, arrived Saturday morning for a ceremony at the National 9/11 Memorial at the spot where the twin towers once stood.
The president and first lady also met with former New York Mayor Michael Bloomberg and his partner Diana Taylor, according to the White House. They were seen greeting FBI director Christopher Wray, House Speaker Nancy Pelosi, the New York congressional delegation and many other current and former state and local officials as they arrived at the memorial.
Vice President Harris and second gentlemen Douglas Emhoff are en route to Shanksville, Pa., where they will mark the morning along with former President George W. Bush and former first lady Laura Bush. Harris and Biden will both be at the Pentagon later this afternoon with their spouses.
The Bidens were also expected to attend wreath-laying ceremonies at the Pentagon and in Shanksville, Pa., where United Airlines Flight 93 crashed. Former President George W. Bush was also due at the Pennsylvania memorial.
Former President Donald Trump released a video message Saturday morning, largely lambasting Biden's handling of the withdrawal from Afghanistan.
See more NPR coverage of the 20th anniversary of the Sept. 11 attacks.
At ground zero, the national anthem was performed in a solemn ceremony and then, in what has become an annual tradition, a moment of silence was observed at 8:46 a.m., when American Airlines Flight 11 crashed into the north tower. Then the names of those who died in the towers were read aloud.
At the west face of the Pentagon — where American Airlines flight 77, with 64 people aboard, including the five hijackers, careened into the side of the massive complex — bagpipers played Amazing Grace. A service there was set for Saturday morning, hosted by Secretary of Defense Lloyd Austin and Chairman of the Joint Chiefs of Staff Army Gen. Mark Milley.
In London, acting ambassador to the United Kingdom Philip Reeker, attended a special changing of the guard at Windsor Castle, where the U.S. national anthem was performed. Reeker said Americans would be "forever grateful" for the "enduring friendship" between the two countries.
Speaking on Friday, Biden said in the days after the attacks in 2001, "we saw heroism everywhere — in places expected and unexpected."
"We also saw something all too rare: a true sense of national unity," he said.
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