Codebreakers chapter 9: Room 40

Room 40 was the cryptanalysis section of the British Admiralty during the first World War. It has humble beginnings, but grew to be not so humble after all, eventually having a big role in ending the war with the decryption of the Zimmerman telegram.

I found this chapter really interesting because it gives a bit of information about how and why intelligence agencies come to be. I’m going to try to sound intelligent for a bit by describing an intelligence agency’s growth in three parts. I actually do not know what I’m talking about here, so take this with a rock of salt.

  1. The Idea
  2. Slow Growth
  3. Carte Blanche
The Idea

Some smart member of the government thinks up $NEW_IDEA; a way to increase the amount of information the government can gather. The motivation for this is usually practical. For example, the government in question might be on a trajectory for war. Regardless of the reason, this clever individual manages to convince someone that $NEW_IDEA is worth investing in.

In the case of the Brits, this step was Admiral Henry F. Oliver convincing Sir Alfred Ewing to put his interest in cryptology to good use by helping them decipher some intercepted naval cryptograms.

Slow Growth

The idea catches on, but the growth is slow. This is mostly a period of learning as the members of this new group slowly figure out what techniques work and what don’t. They refine their craft. They stay lean. They put in extra time. Interest in $NEW_IDEA increases among the government ranks.

In the case of the Brits, this step was Ewing slowly recruiting people to Room 40. This wasn’t his main job though, so he worked on it semi-clandestinely.

Carte Blanche

By a stroke of luck, the members of our group use $NEW_IDEA to deliver some crucial piece of information to government. Everyone is convinced that $NEW_IDEA does indeed work and gives the country a significant advantage over their enemies. This positive publicity leads $POWERFUL_INDIVIDUAL to give the members of our $NEW_IDEA group free rein to do whatever they want.

In the case of the Brits, this step was Room 40 helping win the Battle of Dogger Bank by intercepting and decrypting messages from the German fleet. After this, “Lord FIsher, the new First Sea Lord, gave Ewing carte blanche to get whatever he needed for the betterment of his work” (page 271)


After the step 3, it’s all uphill for our new organization. They have the resources, a proven track record and the backing of the government. This is A Good Thing, because it means good ideas can prove their worth despite internal politics. However, for intelligence agencies, it can rapidly become a dangerous thing because due to their nature, they are kept on the “down-low”. This means little to no oversight. A secretive organization with a big stick does little to ease my natural skepticism.

Is there an alternative? I’m not sure? Intelligence agencies are secretive for a fair reason: You can’t have $ADVERSARY knowing what you are capable of.
So what then?

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