Read "Japan's Longest Day" (the book, not the movie) [1] which is a serious attempt to reconstruct in detail the events leading up to the decision to surrender. Nobody was really in charge. The civilian government didn't control the military. (See "May 15 Incident" for why.) The army and navy didn't get along and had no unified command. The Emperor was respected but mostly an isolated figurehead. The decision making process, which the book describes in detail, makes the current US administration look well-organized.

[1] https://www.amazon.com/Japans-Longest-Pacific-Research-Socie...

I thought this was going to be about Lawrence's unhappiness with special relativity. Cyclotrons have an upper limit on particle velocity. As particles are accelerated, they have more mass, and the cyclotron's elegant balance between inertia and the containment fields is lost. This was the first time relativity had engineering consequences. Lawrence didn't like that, and doubted whether something as abstract as special relativity could affect his machines.

Nobody knew if bombing Japan was going to end the war, including the Supreme War Council in Japan. War Minister Anami wanted to go on with the war after the first atomic bombing, saying the Allies couldn't have more than one bomb. After the second bomb, he signed a surrender document and committed ritual suicide. There was a big Army pro-war fight-to-the-end faction, which tried a last-minute coup attempt to prevent the surrender.[1]

[1] http://www.amazon.com/Japans-Longest-Pacific-Research-Societ...