What is new in this article is that the military attachés in the Japanese embassy were responsible for delaying the transmission.
If this information is true then the Japanese ambassadors Nomura and Kurusu have gotten a bum rap.
They were officials of a country that attacked us without warning and without cause. Neither they, nor their children, nor any of their countrymen have any reason to exist. It is only through our (oft misguided) mercy that Japan exists at all.