David Sharp, an engineer with Lockheed Martin, displays the “Samurai Flyer”, an aviation design inspired by the maple seed, during the Association for Unmanned Vehicle Systems International Conference August 16, 2011 in Washington, DC. Lockheed Martin unveiled the new design and demonstrated vertical takeoff and landing, stable hover, and on-board video streaming of the aircraft during their demonstration. (Photo by Win McNamee/Getty Images)

A competitor looses control of his pancake while racing during the Shrove Tuesday, or Mardi Gras, tradition at the National Cathedral February 21, 2012 in Washington, DC. (Photo by Chip Somodevilla/Getty Images)

A group of people walk on the sea wall as a man kayaks through the flooded parking lot in downtown Annapolis, Maryland, on October 29, 2021. The US National Weather Service implemented a flood watch for the cities of Baltimore and Annapolis as well as Anne Arundel, Baltimore and Howard counties. Washington, DC, and parts of Virginia faced the same alert. (Photo by Jim Watson/AFP Photo)

A man with an American flag on his back and a Biden/Harris campaign flag rides an electronic skateboard through Black Lives Matter Plaza in front of the White House on Election Day, November 3, 2020 in Washington, DC. This year's historic presidential election between President Donald Trump, the incumbent, and Democratic nominee Joe Biden begins to come to a close even though final results are not expected for days to come as states take longer to count historic levels of mail-in ballots. (Photo by Samuel Corum/Getty Images)

The National Thanksgiving Turkey Corn stands by as President Donald Trump speaks during the 73rd annual presentation and pardoning in the Rose Garden at the White House in Washington, November 24, 2020. In the Rose Garden, Trump pardoned the 42-pound turkey named Corn as part of an annual presidential ritual, the sparing of a turkey from American dinner tables on the Thanksgiving holiday. (Photo by Hannah McKay/Reuters)

U.S. Rep. Alexandria Ocasio-Cortez (D-NY) right, embraces Rep. Ilhan Omar (D-MN). Four Democratic progressive Congresswomen make a statement during a press conference at the U.S. Capitol on July 15, 2019 in Washington, DC about President Trump's remarks telling them to “ego back” to their home countries which they deemed “eblatantly racist” attacks. (Photo by Carol Guzy/Imago Images/ZUMA Press)

“The September 11 attacks (called September 11, September 11th or 9/11), were a series of four coordinated suicide attacks against targets in New York City and the Washington, D.C. area on September 11, 2001. On that morning, 19 terrorists from the Islamist militant group al-Qaeda hijacked four passenger jets. The hijackers intentionally crashed two planes into the Twin Towers of the World Trade Center in New York City; both towers collapsed within two hours. Hijackers crashed a third plane into the Pentagon in Arlington, Virginia. When passengers attempted to take control of the fourth plane, United Airlines Flight 93, it crashed into a field near Shanksville, Pennsylvania, preventing it from reaching its intended target in Washington, D.C. Nearly 3,000 died in the attacks”. – Wikipedia

Photo: A firefighter breaks down after the World Trade Center buildings collapsed September 11, 2001 after two hijacked airplanes slammed into the twin towers in a terrorist attack. (Photo by Mario Tama/Getty Images)

Blankets cover the bodies of a woman (right) and a man (left background) hit by a northbound Penn Central train (background) as they waited with a crowd at Pennsylvania Railroad station in Elizabeth, N.J. on June 8, 1968 to view the southbound train carrying the body of Sen. Robert F. Kennedy to Washington. The woman was identified as Mrs. Antoinette Severini, 54, and the man, John Curia (age unavailable), both of Elizabeth. (Photo by AP Photo)