The Japanese did not use the enigma. The Japanese ciphers had worse flaws. For one thing vowels could only replace vowels. The reason was because Japanese telegraph companies charged more for consonants than vowels, and enciphered messages would have contained as many vowels as consonants, rather than a bias for vowels as in natural language. Diplomatic messages were transmitted via commercial cable companies, those in and out of the U.S. via Western Union.
I understand that...
I was merely pointing out that a sharp eye caught a flaw in the code and minds got together to ‘test the system’ and when they proved to be correct, Yamamoto paid for it.
Also had heard that one of the stories Tom Dewey sat on was that he was aware we had broken the Japanese Code and possibly knew about PH in advance - for the sake of National Security - he basically sat on the info rather than use it in the 1944 race.
Imagine today a pol sitting on something as important as that ..... HA...