An 18th Civil Engineer Squadron firefighter hangs a tag with a fallen firefighter on it during a 9/11 Memorial Stair Climb at Kadena Air Base, Japan, Sept. 11, 2021. One of several memorial events during the 20th anniversary of the Sept. 11, 2001, terrorist attacks, the stair climb underscored the motto “Never Forget,” a promise to never forget the events of that day and the first responders who made the ultimate sacrifice. (U.S. Air Force photo by Airman 1st Class Anna Nolte)