Is it true that the Japan’s Secret War Code caused their downfall?
A fatal flaw in the secret war code of the Japanese navy brought it down during the Pacific War, revealed Dr Peter Donovan, an Australian Mathematician. Dr. Donovan is the first to identify the truth about Japan’s operational code JN-25 since archives became available in 1975.
Dr. Donovan discovered that operational code JN-25 used groups of numbers that were multiples of three. For instance, 0009 might have stood for a certain type of fuel oil, he said. This coding system was a flawed system, and this was systematically exploited by the allied forces, according to Dr. Donovan. The Allied code busters easily detected the code, because it had a recognizable pattern. The Japanese navy introduced JN-25 in 1939. But by 1940, code breaker Alan Turing, who also cracked the code of the German submarines in the Atlantic used, had figured the code out. After cracking it, the Allies were beginning to read the code in 1942. The Japanese had revised the code several times but it was still based on the same flawed codebook.
The discovery came too late to prevent Pearl Harbor in 1941, but it gave the Allies an advantage in the Coral Sea Battle of 1942 and knowledge about the Japanese advance in New Guinea. The former was also able to ambush and sink Japanese aircraft carriers in the crucial Battle of the Midway in 1942.
At the peak of the war, around 35,000 people were engaged in the allied code-breaking effort. This involved intercepting Japanese radio waves made from old cash register parts as part of the deciphering process.
Today, the old codes and the methods used to break them are obsolete, thanks to the advances in technology. New codes are virtually unbreakable.