As Germany surrendered in May 1945, the fight in the Pacific raged on with the US planning the invasion of the Japanese home islands (Operation Downfall). This would have been conducted in two parts- X-Day would commence on Nov 1, 1945 as the first amphibious assault for the Fall Offensive and then Y-Day would commence provisionally on Mar 1, 1946 for the Spring Offensive. The atomic bomb effects were still theoretical and there was reluctance on the part of the scientists that created them to use them, advising President Truman of the unknown nature of such power and the potential casualties. Truman went ahead and ordered the nuclear strikes. On Aug 6, 1945 Tibbets flying "Enola Gay" hit Hiroshima at 8:15 AM, detonating the uranium bomb "Lttle Boy" at 2000 ft over the city in an airburst. 40,000 were killed outright, tens of thousands more wounded and tens of thousnads died later from burns and radiation. Almost 5 sq miles of the city was obliterated. The Japanese did not immediately surrender so 3 days later Sweeney in "Bockscar" (filmed by the B-29 Great Artiste) missed Kokura due to cloud cover and moved to the secondary target of Nagasaki which was hit at 11:00 AM with the plutonium bomb "Fat Man" with similar casualties and destruction. Still, the Japanese did not immediately surrendered but started negotiating about surrender and right of Imperial rule postwar- which was rejected. Russia invaded Manchuria on August 8th and so by August 15th with triple threat of Russian and US invasions plus the A-bombs, Japan surrendered informally, then formally on Sept 2, 1945. The third A-bomb (possible codename Red Sunset) was to be dropped during the third week of August but Truman stopped the core from being delivered to Tinian where the bomb was constructed. The B-29 "Bockscar" probably would have performed the duty again as it was equpped to but the target would again be Kokura (which was spared due to surrender). The date probably would have been Aug 22, 1945. And after the effects were known, had X and Y-Days failed, a potential Z-Day might have commenced on aerial bombing with A-bombs exclusively!!!