Defense Secretary Ash Carter shakes hands with Airman 1st Class Spencer Stone after presenting him the Airman’s Medal at the Heroes of the Rails ceremony at the Pentagon, Sept. 17, 2015. Stone received the Airman’s Medal and the Purple Heart for bravery and valor for his heroic actions to thwart a gunman’s attack on a French train in Paris in August 2015. Air Force photo by Scott Ash

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