Before sunrise University of Tennessee at Chattanooga ROTC Graduate Student Trevon Wiggins jogs as he carries the American Flag around Chamberlain Field. From 6 a.m. until 5:00, on Sept. 11, 2019, the American Flag, carried by members of the Military Science Department at the University of Tennessee at Chattanooga, students and staff, continuously circled Chamberlain Field on the University's campus in commemoration of 9/11. (Robin Rudd / AP)
U.S. Army personnel stand amongst nearly 3,000 flags at sunrise Wednesday, Sept. 11, 2019 in Tempe, Ariz. as they listen to the reading of the names of those killed on September 11, 2001. The flags are part of the annual Tempe Healing Field 9/11 memorial. (Matt York / AP)
A man holds a photo of a victim during a ceremony marking the 18th anniversary of the attacks of Sept. 11, 2001, at the National September 11 Memorial, Wednesday, Sept. 11, 2019, in New York. (Mark Lennihan / AP)
Flowers rest on a bench bearing a name in memory of retired U.S. Army Lieutenant Colonel Gary Smith before a ceremony in observance of the 18th anniversary of the September 11th attacks at the Pentagon in Washington, Wednesday, Sept. 11, 2019. (Patrick Semansky / AP)
A woman wipes away tears as she stands next to the north pool prior to a ceremony marking the 18th anniversary of the attacks of Sept. 11, 2001 at the National September 11 Memorial, Wednesday, Sept. 11, 2019 in New York. (Mark Lennihan / AP)
A couple sits quietly prior to the start of a ceremony marking the 18th anniversary of the attacks of Sept. 11, 2001 at the National September 11 Memorial, Wednesday, Sept. 11, 2019, in New York. (Mark Lennihan / AP)
President Donald Trump and first lady Melania Trump hold their hands over their hearts during a rendition of Taps at a ceremony in observance of the 18th anniversary of the September 11th attacks at the Pentagon in Washington, Wednesday, Sept. 11, 2019. (Patrick Semansky / AP)
Chris LeClair, second from left, of Woodbridge, Va., visits the grounds of the National 9/11 Pentagon Memorial with his children Emily, age 12, from left, Melody, age 11, and Ash, age 3, before a ceremony in observance of the 18th anniversary of the September 11th attacks at the Pentagon in Washington, Wednesday, Sept. 11, 2019. LeClair's late father-in-law, U.S. Navy information systems technician Gregg H. Smallwood, was killed inside the Pentagon when American Airlines Flight 77 struck the building. (Patrick Semansky / AP)
Former President George W. Bush, center, pauses in front of Defense Secretary Mark Esper, second from back right, and former Defense Secretary Donald Rumsfeld, after placing a wreath on the grounds of the National 9/11 Pentagon Memorial at the Pentagon in Washington, Wednesday, Sept. 11, 2019, in observance of the 18th anniversary of the September 11 attacks. (Patrick Semansky / AP)
Vice President Mike Pence and second lady Karen Pence, lead the Families of Flight 93 down a path to a 17-ton boulder that marks the crash site of United Flight 93 following the September 11th Flight 93 Memorial Service at the Flight 93 National Memorial in Shanksville, Pa., Wednesday, Sept. 11, 2019, the 18th anniversary of the attacks. (Gene J. Puskar / AP)
Volunteers Jayne Wagner of Shanksville, Pa., left, and Judy Brant of Indian Lakes, Pa., ring bells as part of the Name Presentation and Ringing of Bells Remembrance of crew and passengers on United Flight 93, during the September 11th Flight 93 Memorial Service in Shanksville, Pa., attended by Vice President Mike Pence, Wednesday, Sept. 11, 2019. (Gene J. Puskar / AP)
A Families of Flight 93 member pays respects at the Wall of Names at the Flight 93 National Memorial in Shanksville, Pa. after a Service of Remembrance Wednesday, Sept. 11, 2019, as the nation marks the 18th anniversary of the Sept. 11, 2001 attacks. The Wall of Names honor the 40 people killed in the crash of Flight 93. (Gene J. Puskar / AP)
The county pauses to remember the 9/11 terrorist attacts, Wednesday, Sept. 11, 2019, that happened to New York City, the Pentagon and the downed United Flight 93 in Shanksville, Pa., on September 11, 2001.