Code Girls, Liza Mundy, Hachette, 2017
The history of code breaking is vast, complex and fascinating. There is much more to it than just the story of Alan Turing and Bletchley Park. Two recent books, this one and The Woman Who Smashed Codes examine women code breakers in the US during the first half of the 1900s. I've reviewed the latter elsewhere - it is the story of Elizebeth Friedman, a trailblazer of considerable significance from the period immediately before WWI through WWII. It dovetails in an effective way with Code Girls
Code Girls is the story of the women who were hired by the US Army and Navy to break codes during the war. Rosie the Riveter is the story we're all familiar with, we are less familiar with this story because the work of the Code Girls was a closely held secret. The story of codebreaking and the women who did it is, though, an important one.
Code Girls is not a text in code making or breaking, but it does spend a little time on codes in order to make it clear how challenging the work was. The Army and Navy would spend the war actively recruiting in colleges where women who normally would transition into careers as teachers were instead given an opportunity to contribute to the war effort.
Part of this story ties into the story of Bletchley Park. When the German Navy transitioned to the four rotor Enigma machine, the solution once found exceeded the capacity of the "bombes" used at Bletchley Park for extracting keys. A talented engineer at NCR devised a new, much faster bombe and it was put into service; the machines were fed and cared for by one group of women code breakers. The British would turn all decryption of naval Engima intercepts over to this unit. Mundy tells the story of the women recruited to help assemble the new bombe, many of whom followed the machine into operations.
The story also covers the US code breaking efforts against the various Japanese systems. There are a couple of famous Japanese codes ("Red" and "Purple"), but there were many many more and the Code Girls eventually got into nearly all of them. Frequently the US high command knew more about what was going on at Japanese outposts than the Japanese did.
Mundy examines the lives they lived in the DC area as well - women living on their own in a manner rarely afforded to them before the war changed everything.
This is an excellent, enjoyable and very readable book. Highly recommended.
