Sept 11 20th Anniversary A ceremonial bell rests on a stage podium at the start of ceremonies to commemorate the 20th anniversary of the Sept. 11 terrorist attacks, Saturday, Sept. 11, 2021, at the National September 11 Memorial & Museum in New York. (AP Photo/John Minchillo)Photo by: AP Sept 11 20th Anniversary A memorial flag is brought onto the stage during ceremonies to commemorate the 20th anniversary of the Sept. 11 terrorist attacks, Saturday, Sept. 11, 2021, at the National September 11 Memorial & Museum in New York. (AP Photo/John Minchillo)Photo by: AP Sept 11 Pentagon The Pentagon is illuminated at dawn before ceremonies marking the 20th anniversary of the Sept. 11, 2001, terrorist attacks in Washington, Saturday, Sept. 11, 2021. (AP Photo/J. Scott Applewhite)Photo by: AP Sept 11 Pentagon April Horton, left, Blake Edward Schaffer, 10, and Andrea Stauter, right, sisters and nephew of Petty Officer First Class Edward Earhart, who was killed in the Pentagon on 9/11, pose for a family photo following an observance ceremony at the Pentagon in Washington, Saturday, Sept. 11, 2021, on the morning of the 20th anniversary of the terrorist attacks. Nephew Blake Edward Schaffer was named honoring Earhart. (AP Photo/Alex Brandon)Photo by: AP Joe Biden, Barack Obama, Michelle Obama, Jill Biden President Joe Biden wipes his eye as he attends a ceremony marking the 20th anniversary of the Sept. 11, 2001, terrorist attacks at the National September 11 Memorial and Museum in New York, Saturday, Sept. 11, 2021. Former President Barack Obama, left, and former†first lady Michelle Obama look on. (AP Photo/Evan Vucci)Photo by: AP Sept 11 20th Anniversary New York City mayor Bill de Blasio, left, and former New York City mayor Rudy Giuliani, right, stand beside one another during ceremonies to commemorate the 20th anniversary of the Sept. 11 terrorist attacks, Saturday, Sept. 11, 2021, at the National September 11 Memorial & Museum in New York. (AP Photo/John Minchillo)Photo by: AP Sept 11 20th Anniversary Bagpipers stand at attention during ceremonies to commemorate the 20th anniversary of the Sept. 11 terrorist attacks, Saturday, Sept. 11, 2021, at the National September 11 Memorial & Museum in New York. (AP Photo/John Minchillo)Photo by: AP Sept 11 Pentagon An American flag is unfurled at the Pentagon in Washington, Saturday, Sept. 11, 2021, at sunrise on the morning of the 20th anniversary of the terrorist attacks. The American flag is draped over the site of impact at the Pentagon. (AP Photo/J. Scott Applewhite)Photo by: AP Sept 11 20th Anniversary Flags with red lines to signal support for firefighters are placed beside names of the fallen on the south pool during ceremonies to commemorate the 20th anniversary of the Sept. 11 terrorist attacks, Saturday, Sept. 11, 2021, at the National September 11 Memorial & Museum in New York. (AP Photo/John Minchillo)Photo by: AP Sept 11 Pentagon Secretary of Defense Lloyd Austin, accompanied by Joint Chiefs Chairman Gen. Mark Milley, seated left, speaks during an observance ceremony at the Pentagon in Washington, Saturday, Sept. 11, 2021, on the morning of the 20th anniversary of the terrorist attacks. (AP Photo/Alex Brandon)Photo by: AP Kamala Harris, Douglas Emhoff Vice President Kamala Harris and her husband Douglas Emhoff attend a memorial for the passengers and crew of United Flight 93, Saturday Sept. 11, 2021, in Shanksville, Pa., on the 20th anniversary of the Sept. 11, 2001, attacks. Secretary of Interior Deb Haaland and Gordon Felt, brother of Edward Porter Felt and President of Familes for Flight 93, are right. (AP Photo/Jacquelyn Martin)Photo by: AP Sept 11 20th Anniversary Mourners salute in memory of the fallen before ceremonies to commemorate the 20th anniversary of the Sept. 11 terrorist attacks, Saturday, Sept. 11, 2021, at the National September 11 Memorial & Museum in New York. (AP Photo/John Minchillo)Photo by: AP Joe Biden, Jill Biden, Barack Obama, Michelle Obama Former President Barack Obama, former first lady Michelle Obama, President Joe Biden and first lady Jill Biden attend a ceremony marking the 20th anniversary of the Sept. 11, 2001, terrorist attacks at the National September 11 Memorial and Museum in New York, Saturday, Sept. 11, 2021. (AP Photo/Evan Vucci)Photo by: AP Sept 11 20th Anniversary People react as they attend a ceremony marking the 20th anniversary of the Sept. 11, 2001, terrorist attacks at the National September 11 Memorial and Museum in New York, Saturday, Sept. 11, 2021. (AP Photo/Evan Vucci)Photo by: AP Sept 11 20th Anniversary People react as they attend a ceremony marking the 20th anniversary of the Sept. 11, 2001, terrorist attacks at the National September 11 Memorial and Museum in New York, Saturday, Sept. 11, 2021. (AP Photo/Evan Vucci)Photo by: AP Bruce Springsteen Bruce Springsteen performs during a ceremony marking the 20th anniversary of the Sept. 11, 2001, terrorist attacks at the National September 11 Memorial and Museum in New York, Saturday, Sept. 11, 2021. (AP Photo/Evan Vucci)Photo by: AP Sept 11 20th Anniversary People gather outside the National September 11 Memorial and Museum during a ceremony marking the 20th anniversary of the 9/11 terrorist attacks, Saturday, Sept. 11, 2021, in New York. (AP Photo/Matt Rourke)Photo by: AP APTOPIX Sept 11 20th Anniversary Firefighters from Massachusetts gather with others outside the National September 11 Memorial and Museum during a ceremony marking the 20th anniversary of the 9/11 terrorist attacks, Saturday, Sept. 11, 2021, in New York. (AP Photo/Matt Rourke)Photo by: AP Sept 11 20th Anniversary Port Authority police stand beside the south pool before ceremonies to commemorate the 20th anniversary of the Sept. 11 terrorist attacks, Saturday, Sept. 11, 2021, at the National September 11 Memorial & Museum in New York. (AP Photo/John Minchillo)Photo by: AP Sept 11 Pentagon Joint Chiefs Chairman Gen. Mark Milley, speaks during an observance ceremony at the Pentagon in Washington, Saturday, Sept. 11, 2021, on the morning of the 20th anniversary of the terrorist attacks. An American flag is draped over the site of impact at the Pentagon. (AP Photo/Alex Brandon)Photo by: AP Sept 11 Pentagon An attendee prays during an observance ceremony at the Pentagon in Washington, Saturday, Sept. 11, 2021, on the morning of the 20th anniversary of the terrorist attacks. (AP Photo/Alex Brandon)Photo by: AP Sept 11 Pentagon Attendees listen during an observance ceremony at the Pentagon in Washington, Saturday, Sept. 11, 2021, on the morning of the 20th anniversary of the terrorist attacks. An American flag is draped over the site of impact at the Pentagon. (AP Photo/Alex Brandon)Photo by: AP Sept 11 20th Anniversary Police officers salute at the start of ceremonies to commemorate the 20th anniversary of the Sept. 11 terrorist attacks, Saturday, Sept. 11, 2021, at the National September 11 Memorial & Museum in New York. (AP Photo/John Minchillo)Photo by: AP Sept 11 20th Anniversary A memorial flag is brought onto the stage during ceremonies to commemorate the 20th anniversary of the Sept. 11 terrorist attacks, Saturday, Sept. 11, 2021, at the National September 11 Memorial & Museum in New York. (AP Photo/John Minchillo)Photo by: AP Sept 11 Pentagon An American flag is unfurled at the Pentagon in Washington, Saturday, Sept. 11, 2021, at sunrise on the morning of the 20th anniversary of the terrorist attacks. The American flag is draped over the site of impact at the Pentagon. (AP Photo/J. Scott Applewhite)Photo by: AP APTOPIX Sept 11 20th Anniversary A National Park Service ranger stands in front of the Wall of Names at the Flight 93 National Memorial in Shanksville, Pa. before a Service of Remembrance Saturday, Sept. 11, 2021, as the nation marks the 20th anniversary of the Sept. 11, 2001 attacks. (AP Photo/Gene J. Puskar)Photo by: AP Sept 11 Pentagon An American flag is unfurled at the Pentagon in Washington, Saturday, Sept. 11, 2021, at sunrise on the morning of the 20th anniversary of the terrorist attacks. The American flag is draped over the site of impact at the Pentagon. In the foreground, the National 9/11 Pentagon Memorial, opened in 2008 adjacent to the site, commemorates the lives lost at the Pentagon and onboard American Airlines Flight 77. (AP Photo/Alex Brandon)Photo by: AP Sept 11 Pentagon An American flag is unfurled at the Pentagon in Washington, Saturday, Sept. 11, 2021, at sunrise on the morning of the 20th anniversary of the terrorist attacks. The American flag is draped over the site of impact at the Pentagon. In the foreground, the National 9/11 Pentagon Memorial, opened in 2008 adjacent to the site, commemorates the lives lost at the Pentagon and onboard American Airlines Flight 77. (AP Photo/Alex Brandon)Photo by: AP Sept 11 20th Anniversary A mourner places a flag at the south pool before ceremonies to commemorate the 20th anniversary of the Sept. 11 terrorist attacks, Saturday, Sept. 11, 2021, at the National September 11 Memorial & Museum in New York. (AP Photo/John Minchillo)Photo by: AP Sept 11 Pentagon An American flag is unfurled at the Pentagon in Washington, Saturday, Sept. 11, 2021, at sunrise on the morning of the 20th anniversary of the terrorist attacks. The American flag is draped over the site of impact at the Pentagon. (AP Photo/J. Scott Applewhite)Photo by: AP APTOPIX Sept 11 20th Anniversary Flag bearers rehearse before ceremonies to commemorate the 20th anniversary of the Sept. 11 terrorist attacks, Saturday, Sept. 11, 2021, at the National September 11 Memorial & Museum in New York. (AP Photo/John Minchillo)Photo by: AP Sept 11 Anniversary Tribute in Light The Tribute in Light rises above the World Trade Center Transportation Hub, Friday, Sept. 10, 2021, in New York. Saturday marks the twentieth anniversary of the attacks of Sept. 11, 2001. (AP Photo/Mark Lennihan)Photo by: AP 9/11 Pentagon A beam of light is visible over the Lincoln Memorial, the day before the 20th anniversary of the Sept. 11 terrorist attacks, as part of the Towers of Light Tribute near the Pentagon, Friday Sept. 10, 2021, in Washington. (AP Photo/Jose Luis Magana)Photo by: AP Sept 11 20th Anniversary A visitor to the Flight 93 National Memorial visitor center, in Shanksville, Pa, stand on an observation platform overlooking the crash site of Flight 93 at sunset Friday, Sept. 10, 2021, as the nation prepares to mark the 20th anniversary of the Sept. 11, 2001 attacks. (AP Photo/Gene J. Puskar)Photo by: AP Sept 11 Anniversary The World Trade Center is shown on the evening of Friday, Sept. 10, 2021, in New York. Saturday marks the 20th anniversary of the attacks of Sept. 11, 2001. (AP Photo/Mark Lennihan)Photo by: AP APTOPIX Sept 11 20th Anniversary Visitors to the Flight 93 National Memorial in Shanksville, Pa., participate in a sunset memorial service, Friday, Sept. 10, 2021, as the nation prepares to mark the 20th anniversary of the Sept. 11, 2001, attacks. (AP Photo/Gene J. Puskar)Photo by: AP Sept 11 Anniversay People visit the National September 11 Memorial and Museum ahead of the 20th anniversary of the 9/11 terrorist attacks, Friday, Sept. 10, 2021, in New York. (AP Photo/Matt Rourke)Photo by: AP Sept 11 Anniversary Visitors browse the south pool as flowers and American flags rest among the names of the fallen at the National September 11 Memorial & Museum, Thursday, Sept. 9, 2021, in New York. (AP Photo/John Minchillo)Photo by: AP Sept 11 Anniversary A visitor takes a photograph of flowers and American flags resting among the names of those who died at the National September 11 Memorial & Museum, Thursday, Sept. 9, 2021, in New York. (AP Photo/John Minchillo)Photo by: AP Sept 11 Anniversary Kathy Birch, sister of Charles Gregory "Chuck" Costello Jr., an elevator electrician who ran into Tower 1 of the World Trade Center before the towers fell, stands beside her brothers name while visitors browse the north pool at the National September 11 Memorial & Museum, Thursday, Sept. 9, 2021, in the Manhattan borough of New York. (AP Photo/John Minchillo)Photo by: AP Sept 11 Anniversary Retired Santa Clara firefighter Darrell Sales, right, and fellow cyclist Jeremy Provancher, left, stand beside the south pool holding an American flag after completing their "Bay to Brooklyn" bicycle ride at the National September 11 Memorial & Museum, Thursday, Sept. 9, 2021, in New York. A team of current and former firefighters spent 40 days traveling by bicycle to New York City in solidarity for the 20th anniversary of the September 11 terrorist attacks. (AP Photo/John Minchillo)Photo by: AP Sept 11 Anniversay Police officers stand guard at the National September 11 Memorial and Museum ahead of the 20th anniversary of the 9/11 terrorist attacks, Friday, Sept. 10, 2021, in New York. (AP Photo/Matt Rourke)Photo by: AP Sept 11 Anniversay A person touches an inscribed name at the National September 11 Memorial and Museum ahead of the 20th anniversary of the 9/11 terrorist attacks, Friday, Sept. 10, 2021, in New York. (AP Photo/Matt Rourke)Photo by: AP Sept 11 Anniversary Flowers and American flags rest among the names of the fallen on the south pool at the National September 11 Memorial & Museum, Thursday, Sept. 9, 2021, in the Manhattan borough of New York. (AP Photo/John Minchillo)Photo by: AP Sept 11 Anniversary Military personnel on shore leave browse the north pool at the National September 11 Memorial & Museum, Thursday, Sept. 9, 2021, in New York. (AP Photo/John Minchillo)Photo by: AP Sept 11 Anniversary Military personnel on shore leave browse the pool at the National September 11 Memorial & Museum, Thursday, Sept. 9, 2021, in the Manhattan borough of New York. (AP Photo/John Minchillo)Photo by: AP Sept 11 Anniversary A visitor pauses at the north pool as the sun sets over the National September 11 Memorial & Museum, Wednesday, Sept. 8, 2021, in the Manhattan borough of New York. (AP Photo/John Minchillo)Photo by: AP Joe Biden, Jill Biden, Kamala Harris, Doug Emhoff President Joe Biden, first lady Jill Biden, Vice President Kamala Harris and her husband Douglas Emhoff, participate in a wreath ceremony on the 20th anniversary of the terrorist attacks at the Pentagon in Washington, Saturday, Sept. 11, 2021, standing at the National 9/11 Pentagon Memorial site, which commemorates the lives lost at the Pentagon and onboard American Airlines Flight 77. With the President, not shown, are Secretary of Defense Lloyd Austin and Joint Chiefs Chairman Gen. Mark Milley and his wife Hollyanne Milley. (AP Photo/Alex Brandon)Photo by: Alex Brandon/AP Joe Biden, Jill Biden President Joe Biden and first lady Jill Biden participate in a wreath ceremony on the 20th anniversary of the terrorist attacks at the Pentagon in Washington, Saturday, Sept. 11, 2021, standing at the National 9/11 Pentagon Memorial site, which commemorates the lives lost at the Pentagon and onboard American Airlines Flight 77. With the President, not shown, are Vice President Kamala Harris and her husband Douglas Emhoff, Secretary of Defense Lloyd Austin and Joint Chiefs Chairman Gen. Mark Milley and his wife Hollyanne Milley. (AP Photo/Alex Brandon)Photo by: Alex Brandon/AP