Air Force Chief of Staff Gen. David L. Goldfein (left) shakes hands with Tech. Sgt. Daniel Keller, a combat controller in the 123rd Special Tactics Squadron, during a ceremony at the Kentucky Air National Guard Base in Louisville, Ky, Aug.13, 2019. Earlier in the ceremony, Goldfein presented Keller with the Air Force Cross, which Keller earned for valor on the battlefield in Afghanistan. (U.S. Air National Guard photo by Dale Greer)