Tuesday, November 11, 2014

The World War II Code Breakers Next Door - Discovering Arlington Hall

The year is 1942. The allies are hard at work trying to crack the coded messages of both the Germans and Japanese. And where, do you suppose, was the largest message center in the world at that time? Why, right here in Arlington, VA. The location is known as Arlington Hall (or Arlington Hall Station). These days, the entrance to US Army National Guard Readiness Center is as close as I can get to it:

The work at Arlington Hall and cryptography at that time in general, was mighty impressive. For one thing, back in 1942 the term computer was a job description, much like a teacher or plumber. And the number of individuals involved was quite large:

By the end of World War II approximately 8,000 civilian and military employees worked at Arlington Hall Station on twenty-four-hour, six-day-a-week schedule.

Though, as you can see from photo below, even then IBM was on the case!

There was nothing casual about the work being completed at the site:

Women accepted into the cryptographic field were sworn to secrecy. The penalty for discussing the work outside of approved channels could be death, as it was considered an act of treason during a time of war. One Wac still recalled more than fifty years later, the first lecture she received: “Don’t talk.” The Army informed her and her fellow Wacs that no one was to know of their work. Anyone caught discussing it would be treated as a spy and shot. The Navy gave their WAVES the same warning.

But it wasn't just brute force work that was completed at Arlington Hall. The Japanese Army codes were cracked thanks to the individual's working at the Hall. One source sums it up this way:

Communications intelligence provided by Arlington Hall was the Army's most important single source of information during World War II.

I simply never knew.

And then there are the women. Unlike most jobs in the military, cryptography was "never a traditionally male job." So it was no surprise that many women worked at Arlington Hall and significantly contributed to the effort.

But these weren't just nameless worker bees. Consider this snapshot:

On the surface, this looks like another photo of nameless women hard at work in Arlington Hall. However, the individual in the front right is none other than Ann Caracristi. Consider her career track:

Ann Caracristi came to work as a cryptanalyst with the Army Signal Intelligence Service in 1942. Initially, she sorted Japanese Army messages but quickly advanced to cryptanalysis and then supervision. She helped pioneer the application of early computers in cryptanalysis and established a laboratory for studying new communications phenomena.

Her expertise and professionalism responding to tough intelligence problems brought her rapid advancement at NSA. In 1959, she was promoted to supergrade and in 1975, she became the first woman at NSA to be promoted to GS-18. She was the first woman to be named NSA Deputy Director in 1980. Also in 1980, she received the Department of Defense Distinguished Civilian Service Award, the DoD's highest civilian honor.

From message sorting to NSA Deputy Director, impressive, no?

Arlington Hall's history doesn't stop with the end of WW II. The origins of both the DIA and NSA can be found there. And then there's project Venona, which involved decoding messages from the Soviet Union. Though, that's another post for another day.

So next time you drive by 4000 Arlington Boulevard take a moment to realize just how pivotal this site was to the survival and success of our nation at war. And how 50 years before Barbie declared 'math class is tough' women were using math to save lives and alter the course of history.


  1. Anonymous2:45 PM

    My mother was a WAC at Arlington Hall during the war. I never even knew she had been in the Army till I was in my teens, and she rarely spoke of what she did, and never in any detail. And then she worked for years at NSA. All classified, and she kept her promise, right to her death.

  2. Wow - thanks for sharing! It's a shame her story isn't (can't be?) well known. Still, I very much appreciate her service to our country.