On Jan. 29, 1945, First Sgt. Leonard Funk, Jr. faced a determined German army officer ready to kill him with a pistol. Armed with a Thompson M1A1 submachine gun, the U.S. Army paratrooper had just led an assault against 15 houses occupied by German troops in Holzheim, Belgium. It was part of an operation by the 82nd Airborne Division to clear German soldiers from the area following the Battle of the Bulge. Leading a makeshift headquarters platoon of clerks, Funk and his unit captured 30 prisoners. He left them with several dozen more prisoners—under guard—and returned to the fight. While...