[Bill] Binney will argue with you all day about ThinThread, but his idea was that it would collect everything about everybody but be immediately encrypted so no one could read it. Only a court could give intelligence officials the key to decrypt it. The idea was to find a kind of a compromise between [privacy rights and] the assertion that if you don't collect things as they happen, you won't have them later - because what the NSA really wants is the capability of retrospective investigation.