The Secret Weapon that Won World War II

DID YOU KNOW? On November 23, 1940, Romania signs the Tripartite Pact, officially allying itself with Germany, Italy, and Japan.


America's lesser known secret weapon caused even more destruction than the atomic bomb. Called Operation Magic, this weapon was military and diplomatic intelligence, and its chief practitioner was Commander Joseph J. Rochefort, an eccentric army officer who dressed in a velvet smoking jacket and slippers.

The Signal Intelligence Service (SIS) was the branch of the US Army responsible for cracking other countries' codes--including those of America's allies. It had been working to break Japan's diplomatic code since the late 1920s, and in 1937, it finally succeeded. In fact, most of Japan's encrypted messages were being deciphered when the Pacific war began four years later. Commander Rochefort, the man behind this operation, had his hollow-eyed, often unshaven staff working on their IBM tabulating machines around the clock. Because he, too, would stay locked in his office for days at a time, Rochefort made sure to dress comfortably.

"Magic" tipped the Japanese Imperial Navy's hand at the battle of Midway and other naval engagements, and enabled American submarines to locate (and sink) thousands of Japanese cargo ships. Another key success was deciphering the itinerary of an inspection tour Japan's Admiral Isoroku Yamamoto was planning to make of bases in the South Pacific. US fighter planes shot down the admiral's plane as a result and deprived Japan of its most respected military leader.

Although regular army and navy types seldom knew what to make of brilliant but eccentric codebreakers like Rochefort, the work of these unsung heroes was essential in securing Allied victory in the Pacific. Sometimes, it seemed like they truly could work magic.