Sitting at the kitchen table in the small cottage where I lived in Berkeley with my wife and two cats, I decrypted it.

The anonymous emailer wanted to know if I could help him communicate securely with Laura Poitras, the documentary filmmaker who had repeatedly cast a critical eye on American foreign policy.

From: anon108@????????? To: Micah Lee Date: Fri, 11 Jan 2013

Micah,

I'm a friend. I need to get information securely to Laura Poitras and her alone, but I can't find an email/gpg key for her.

Can you help?

I didn't know it at the time, but I had just been contacted by Edward Snowden, the National Security Agency contractor who was then preparing a momentous leak of government data.

A month earlier, Snowden had anonymously emailed Glenn Greenwald, a Guardian journalist and chronicler of war-on-terror excesses, but Greenwald didn't use encryption and didn't have the time to get up to speed, so Snowden moved on. As is now well known, Snowden decided to contact Poitras because she used encryption. But he didn't have her encryption key, as is necessary to send someone encrypted email, and the key wasn't posted on the web. Snowden, extraordinarily knowledgeable about how internet traffic is monitored, didn't want to send her an unencrypted email, even if just to ask for her key. So he needed to find someone he thought he could trust who both had her key and used encrypted email.

That was me.