What Japanese unit was commanded by the admiral targeted by Operation Vengeance?
John W. Mitchell (United States Air Force): John William Mitchell (14 July 1915 – 15 November 1995) was an officer of the United States Air Force, a flying ace and the leader of Operation Vengeance, the mission to shoot down Admiral Isoroku Yamamoto. Isoroku Yamamoto: Isoroku Yamamoto (山本 五十六 , Yamamoto Isoroku , April 4, 1884 – April 18, 1943) was a Japanese Marshal Admiral of the Navy and the commander-in-chief of the Combined Fleet during World War II until his death.
the Combined Fleet