'Code Girls' Tells Untold Story of WWII Women Code Breakers

The war service of millions of "Rosie the Riveter" factory workers who helped build bombers, tanks, and aircraft carriers is well known, but the 10,000 female code breakers who worked in operations that presaged the National Security Agency have gone unrecognized — until now.

In a book released Tuesday, "Code Girls: The Untold Story of the American Women Code Breakers of World War II," author Liza Mundy reported female code breakers ran complex office machines converted to code-breaking purposes, built libraries of public speeches, shipping inventories, and lists of ship names and enemy commanders that helped break messages and illuminate their content, and worked as translators.

"Their work saved thousands of precious lives," Rep. Clarence Hancock of New York declared on the floor of the House on Oct. 25, 1945, about WWII code breakers.

"I believe that our cryptographers . . . in the war with Japan did as much to bring that war to a successful and early conclusion as any other group of men."

That more than half of these "cryptographers" were women was nowhere mentioned, according to Mundy.

In a piece for Politico Magazine, Mundy wrote the Navy did not allows its female code breakers serve overseas but the Army did, sending them to Australia and the Pacific Islands, and even with Gen. Douglas MacArthur when he occupied Tokyo after the war.

Other women helped create "dummy traffic," she wrote — fake radio signals that helped fool the Germans into believing the D-Day invasion would take place in Norway or the Pas-de-Calais region of France — rather than on the beaches of Normandy.

"It was generally believed that women were good at doing tedious work — and as I had discovered early on, the initial stages of cryptanalysis were very tedious, indeed," Ann Caracristi, whose first job as a code breaker was sorting reams of intercepted traffic, told Mundy.

The code breakers of World War II advanced what is known as signals intelligence—reading the coded transmissions of enemies, and sometimes of allies, laying the groundwork for the field of cybersecurity, and pioneer work that led to the modern computing industry, Mundy wrote.

After the war, the Army and Navy code-breaking operations merged to become what is now the NSA — and it was women who helped found the field of clandestine eavesdropping, and in many case who shaped the early culture of the NSA, Mundy wrote.

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