The outcome of the Pacific War turned on a canteen of fresh water.
The United States had broken the Japanese JN-25 Naval code. We knew they were up to something; something to do with a place they designated “AF.” We just didn’t know where “AF” was. In those terrifying early months of war we couldn’t risk being out of place with what remained of our fleet while they pounced somewhere unexpected. We needed to unpuzzle “AF.”
In the spring of 1942, Japanese intercepts began to make references to a pending operation in which the objective was designated as “AF.” Rochefort and Captain Edwin Layton, Nimitz’s Fleet Intelligence Officer, believed “AF” might be Midway since they had seen “A” designators assigned to locations in the Hawaiian Islands. Based on the information available, logic dictated that Midway would be the most probable place for the Japanese Navy to make its next move. Nimitz however, could not rely on educated guesses.
In an effort to alleviate any doubt, in mid-May the commanding officer of the Midway installation was instructed to send a message in the clear indicating that the installation’s water distillation plant had suffered serious damage and that fresh water was needed immediately. Shortly after the transmission, an intercepted Japanese intelligence report indicated that “AF is short of water.”
By the end of the day – June 4, 1942 – four Japanese aircraft carriers were at the bottom of the Pacific Ocean and the Allied forces had gained a measure of naval supremacy in the Far East.
I think about Midway a good bit – partly because I vaguely remember seeing the movie when I was little kid and partly because the cryptology part of the story is so much fun – but every year I’m surprised when I hear that June 4 is the anniversary of the Battle of Midway. Not next year, though. I’ve set myself a reminder.