On Nov. 1, 2007, the National Security Agency hosted a talk by Roger Dingledine, principal designer of one of the world's leading Internet privacy tools. It was a wary encounter, akin to mutual intelligence gathering, between a spy agency and a man who built tools to ward off electronic surveillance.
According to a top secret NSA summary of the meeting, Dingledine told the assembled NSA staff that his service, called Tor, offered anonymity to people who needed it badly — to keep business secrets, protect their identities from oppressive political regimes or conduct research without revealing themselves. In the minds of NSA officials, Tor was offering protection to terrorists and other intelligence targets.
As he spoke to the NSA, Dingledine said in an interview Friday, he suspected the agency was attempting to break into Tor, which is used by millions of people around the world to shield their identities. Documents provided by ex-agency contractor Edward Snowden show he was right.