On December 7,1941 Japan attacked and destroyed most of the US Navy fleet based at Pearl Harbor. In many ways the bloody war in the pacific was a combat of codes. In late 1941, the American leadership was aware of the tensions with Japan because we were able to read most of the diplomatic and military communications.
However, the attack on Pearl Harbor was not made available in the Japanese coded traffic. The US Army broke into the highest level of Japanese diplomatic cypher - code named "PURPLE" - well before the attack on Pearl Harbor. Yet, PURPLE produced little of military value, as the Japanese Foreign Ministry was considered unreliable by the Tokyo political leadership.
The strike, devised and led by the brilliant Japanese Naval commander, Admiral Isoruko Yamamoto, crippled the American fleet, killing over 2,000 Americans, and sinking nine US Navy battleships.
In 1941, the battleship was considered to be the most powerful weapon of war. In the 1920s, US Navy "Battleship" Admirals were the most powerful force in America's military command. The Battleship admirals led an effort to disgrace airpower advocate General Billy Mitchell because he predicted that tiny airplanes could sink the mighty battleships. Mitchell knew of the coming science in flight and that aircraft would soon dominate. The entrenched naval command would have nothing of this new idea and hounded Mitchell out of the service in 1926.
On December 7, 1941, in the span of a few short minutes, Admiral Yamamoto demonstrated that Mitchell was right. Fortunately, Yamamoto missed the US Navy aircraft carriers which were out on exercises that day. Yet, the devastating attack propelled America into World War II.
Read the entire article