Time has revealed two more atomic bomb projects. Germany was doing its best to develop one, but the Brits and we knew it. We delayed their heavy water project in Norway and elsewhere. They had moved enriched uranium to Normandy in preparation of dropping dirty bombs on London and later, New York. The Normandy invasion stopped this plan. They also had packed a super submarine with enriched uranium and jets to be sent to Japan. It was enroute when Germany surrendered and the sub surrendered and was delivered to Boston. Two Japanese officers aboard committed suicide when they discovered they would not make Japan.
The Japanese had two different atomic bomb projects. One by their Army and one by their Navy. The Navy project was destroyed during bombing in Tokyo. The Army project continued on in Korea and is suspected to have produced a small test explosion the day the Japanese surrendered. The Japanese also had super submarines which contained several bombers with which they planned to bomb the Panama Canal which plan was later changed to bomb San Francisco with dirty bombs.
We did not know how close each country was to attacking allies with dirty bombs. We were planning on a Naval invasion of Japan. The plan involved attacking the lower part of the Southernmost Japanese island. Plans of the day involved attacking with three times the number of protectors in order to be successful. We knew only just before the planned attack the the number would be more like 50-50 and the Japanese were heavily fortified in tunnels and caves. The estimated casualties was 1 million allies. We are still using the purple hearts struck for that last battle over 60 years later. We also had thousand of tons of chemical weapons which the Army was planning to use. The plan was being changed at the last to consider a different landing area (possibly North island) dur to the strength of Japanese in the South. The Japanese military was unconcerned with the starvation that would result in Japan. Their plan was to delay delay delay until the allies grew tired of the war and the Japanese could sue for a better peace.
The atomic bomb saved many millions of people.