U.S. President Donald Trump speaks during a ceremony held at the Flight 93 National Memorial, marking the 17th anniversary of the Sept. 11 attacks, in Shanksville, Pennsylvania, the United States, Sept. 11, 2018. (Photo/Xinhua)
People ring the bells to commemorate the victims of the Flight 93, marking the 17th anniversary of the Sept. 11 attacks, at the Flight 93 National Memorial, in Shanksville, Pennsylvania, the United States, Sept. 11, 2018. (Photo/Xinhua)
Children play among U.S. national flags erected to honor the victims of the September 11, 2001 attacks in New York, at the campus of Pepperdine University in Malibu, the United States, Sept. 10, 2018. (Photo/Xinhua)
People walk among U.S. national flags erected to honor the victims of the September 11, 2001 attacks in New York, at the campus of Pepperdine University in Malibu, the United States, Sept. 10, 2018. (Photo/Xinhua)
