This Memorial Day, History.com salutes Sergeant Hjalmar Johansson, a first-generation Swedish American who at just 17 years old volunteered for the U.S. Army Air Corps. During his very first mission as a nose gunner on a B-24 bomber, Johansson’s plane was shot down by the Germans. What followed was a harrowing six months in Nazi prison camps during which he experienced extreme hunger, brutality and isolation. Now 90 years old, Johansson is the only surviving member of his bomb group, and he tours the country sharing his thoughts on patriotism and the cost of freedom.