It was 8:15 on a Monday morning, Aug. 6, 1945. World War II was raging in Japan and across Europe. An American B-29 bomber dropped the world’s first atomic bomb over Hiroshima, Japan – an important military center with a civilian population close to 300,000 people. The U.S. wanted to end the war, and Japan was unwilling to surrender unconditionally. The bomber plane was called the Enola Gay, named for Enola Gay Tibbets, the mother of the pilot. Its passenger was “Little Boy” – an atomic bomb that quickly killed 80,000 people in Hiroshima. Tens of thousands more would later...