PHOTOS: September 11th Remembrance Ceremonies
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AP Photo/Jared Wickerham
A visitor pays tribute to the passengers and crew of Flight 93 at the Flight 93 National Memorial in Shanksville, Pa, Sunday, Sept. 11, 2016.
The U.S. marked the 15th anniversary of 9/11 on Sunday, with victims' relatives reading their names and reflecting on a loss that still felt as immediate to them as it was indelible for the nation.