An empty Pearl Harbor still offers fixed infrastructure targets and could be struck to lure the Pacific Fleet north. Hunting the fleet, however, promises permanent ship losses rather than wrecks that can be raised from shallow harbor water. Deep Pacific water also removes the special shallow-drop problem that forced Japan to modify its aerial torpedoes for the historical raid. Japan lacked the British tension-wire solution but had fitted stabilizing fins, making open-water attacks the easier technical case. The preference for finding the fleet also fits the Japanese desire for a decisive engagement, just as other navies' doctrines reflected unresolved lessons and frustrations from the First World War.
Notable Point · 50:03-53:24
Japan's choice: attack the base or hunt the fleet
Pearl Harbor is easier to locate, but ships sunk in deep water stay lost and Japanese torpedoes work better away from the shallow anchorage.