The Japanese also tended to put units of the Fleet into reserve for various periods of time. Sometimes for refit, which would usually take a year or longer, and sometimes not. One way to help reduce operating expenses.
While Wilson's decision to insist upon a uanaimous vote, after the proposal had already received a majority approval, angered the Japanese public. What really angered the Japanese was the British, whom they had whole heartedly supported in the war (WWI). Even meeting British requests for naval units, which when dispatched left the Japanese home islands vulnerable, in their opinion. Japan felt they had held up their end of the bargain and all they wanted was to be treated as equals. Britain really didn't have much of a problem with the proposal, but Australia was strongly opposed to it. In order to keep Australia happy, Britain opposed the resolution. Japan's representative to the Paris Peace Conference, Makino Nobuaki had this to say in regards to the slight: We are not too proud to fight but we are too proud to accept a place of admitted inferiority in dealing with one or more of the associated nations. We want nothing but simple justice.
The Americans had broke the Japanese code and knew they would accept the lower number so they insisted on it.
Weeeeellll.... I don't think is was "codebreaking" per se, but "breaking and entering." But, yes, the Americans were reading the Japanese coded material, and this did give them a leg up in the negotiations.
Please don't post links without any information as to what they contain. Hard to tell if it's legitimate or spam/scam related.
The treaty actually led Japan to the rule by assassination period. The nationalist felt sold out by the treaty, not understanding that America could easily out build Japan. The ultra right felt that Japan had been cheated of her rightful place and thus began assassinating officials they felt did not show the proper devotion to Japans right spot.