Japanese Admirals Mocked Submarines… Until America Destroyed Their Merchant Fleet
In the years before World War II, many leaders in the Imperial Japanese Navy believed submarines were a secondary weapon. Their strategy focused on massive battleships and a single decisive naval battle that would determine the fate of the Pacific.
But while Japanese admirals prepared for legendary fleet engagements, a different kind of war was beginning beneath the ocean.
American submarines quietly targeted Japan’s merchant fleet — the cargo ships and oil tankers that carried fuel, food, and raw materials across the empire. These vessels were the lifeline that kept Japan’s industry running and its military supplied.
By 1943, once early torpedo problems were fixed, U.S. Navy submarines began sinking Japanese shipping at an astonishing rate. Convoys burned across the Pacific. Tankers carrying precious oil disappeared beneath the waves. Entire supply routes collapsed.
By the end of the war, American submarines had destroyed more than half of Japan’s merchant fleet. Factories slowed, fuel vanished, and the mighty Imperial Navy found itself unable to move or fight.
What began as a weapon many Japanese commanders dismissed would ultimately help suffocate an entire empire.
This episode from WW2 STORIES – War Tales & Untold History explores the silent campaign beneath the Pacific: the submarine war that crippled Japan’s economy and changed the course of World War II.
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