BERGEN-BELSEN, Germany — They call him the ultimate survivor: Shaul Ladany lived through a Nazi concentration camp and escaped the massacre of 11 fellow Israeli athletes at the 1972 Olympic Games in Munich. “I always bring here one of my relatives to teach them, to educate them what happened,” Ladany said. The Ladanys fled Belgrade in 1941 after their home was bombed by the German Luftwaffe, or air force. They escaped to Budapest, Hungary, but were eventually captured by the Nazis and sent to Bergen-Belsen, where 52,000 prisoners — mostly Jewish — were killed, or died shortly after its liberation...