IJN at time of Pearl Harbor Attack in December 1941:
(1) Ibuki ordered but not laid down (2) Mogamis designated light cruisers but were built to be up-gunned as heavies once the London Naval Treaty was broken.
(1) 27 Yūgumo class and 16 Akizuki-class building (2) Others ships of the Momi-class were re-rated as patrol vessels. Also, note than Momi name was assigned in 1944 to a Matsu-class destroyer ship
Many under direct navy control as armed merchantmen.
Imperial Japanese Navy commanders at the time of the Attack on Pearl Harbor:
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