Did a secret Japanese research program during World War II construct its own atomic weapon, which was actually tested in North Korea a day or two after Nagasaki and then captured by the invading Russians?
The answer, I'm afraid, is probably "no", but the author has discovered a remarkable story. I was left in no doubt that a Japanese version of the Manhattan Project did exist. It's rather moving in a strange way, and I was reminded several times of
Das Boot. Just as with the movie, where after a while you realise you're identifying with the crew of the U-boat and cheering them on as they sink Allied convoy ships, I found myself hoping that Professor Nishina and his team would somehow succeed.
They had some real stars on their side: Yukawa, who got a Nobel Prize for discovering the meson, and Tomonaga, who later made major contributions to quantum electrodynamics and helped work out the renormalisation method. Nishina himself comes across as a great man, who just happened to end up fighting on the wrong side. But they never received enough funding, and they couldn't get their hands on sufficient quantities of uranium, despite valiant efforts. Also, they chose the wrong method for trying to separate out U-235 from U-238. Thermal diffusion didn't turn out to work, though everyone would have called it a stroke of genius if it had. They did eventually start building large centrifuges, but then the firebombing started and it was too late.
In the parallel universe described in
Man In The High Castle, I wonder if Kawabata writes a novel about this project instead of
The Master of Go? I'm trying to imagine the plot. I think Nishina, who died of cancer a few years after the end of the war, is the figure corresponding to the Master; Arakatsu, his shadowy and apparently rather more pragmatic rival in the parallel Navy-run project, is Otake. There's a subplot in Wilcox's book about a Spanish spy ring in the US who unsuccessfully try to penetrate the American nuclear program; here, I'm guessing that they succeed, and Arakatsu is able to use their stolen knowledge to win the race.
I've already half-convinced myself that the book exists. Perhaps I will get some yarrow stalks and see if I can cross over the other side for long enough to locate a copy.