At this point, no one will be surprised to learn that the NSA can spy on just about everyone, but the latest news from the files of Edward Snowden is still pretty staggering. The Washington Post reports that the NSA is collecting about 5 billion records a day on the location of cellphones overseas. Even when people aren't making calls or sending texts, their mobile devices are connecting to the cellular network. Once that data is collected, an analytic tool known as CO-TRAVELER can determine when an unknown cell user's movements correspond with those of an intelligence target, allowing the NSA to identify a target's associates. "Burner" phones are also useless, since CO-TRAVELER can determine when a new phone connects to a cell tower shortly after another one is discarded. The effect, according to the Post, is that "the agency is able to render most efforts at communications security effectively futile."
As with other NSA surveillance programs, the agency can only legally collect information on foreign targets. It still scoops up the locations of Americans' cellphones "incidentally," but officials suggest they're too preoccupied with catching terrorists to keep track of Americans' boring day-to-day affairs.
Even if the agency isn't making note of who's meeting up with someone who isn't their spouse at seedy motels, privacy advocates say the collection of location data is particularly sensitive. Chris Soghoian, principal technologist at the American Civil Liberties Union, explains that such data allows the NSA to track people even when they've tried to encrypt their e-mails and hide their identities. "The only way to hide your location is to disconnect from our modern communication system and live in a cave," said Soghoian. We suppose that means aluminum foil and an LED cap aren't going going to cut it.