It was a long time ago but I remember Fermi decided that he (Yang) didn't do well at experimental physics, saying "where there's a Yang, there's a bang". My impression was that the atomic bomb wasn't a surprise, with the idea that when the ship arrived he'd enter a new world as a result. He was Oppenheimer's assistant at Princeton. I don't think I knew that at the time, so he must have told me but I don't recall any details. We also had a discussion about Maxwell but his later article on the subject is a much better source than my fading memory.