Which Japanese spy in Honolulu gathered intelligence before the Pearl Harbor attack?

Takeo Yoshikawa was the Japanese spy in Honolulu who gathered intelligence before the Pearl Harbor attack.

Yoshikawa arrived in Hawaii in March 1941 and worked under diplomatic cover at the Japanese consulate in Honolulu. Using the alias Tadashi Morimura, he observed naval activity around Pearl Harbor and reported details to Japanese officials in Tokyo. His reports included information about ship movements, harbor conditions, and American defenses.

He was not a pilot or a commander of the attack force. The operational plan was developed and executed by senior Japanese naval officers, including Admiral Isoroku Yamamoto and carrier-force commander Chuichi Nagumo. Yoshikawa’s role was intelligence collection from inside Hawaii.

The attack began on December 7, 1941, before Yoshikawa could be arrested. The United States detained Japanese diplomats after the attack, and Yoshikawa was later repatriated to Japan through a prisoner exchange. His work is often confused with the broader Japanese espionage network operating in Hawaii.