What’s missing from much of the discussion about the NSA’s activities is what they’re doing with all of this surveillance data. The newspapers focus on what’s being collected, not on how it’s being analyzed — with the singular exception of the Washington Post story on cell phone location collection. By their nature, cell phones are tracking devices. For a network to connect calls, it needs to know which cell the phone is located in. In an urban area, this narrows a phone’s location to a few blocks. GPS data, transmitted across the network by far too many apps, locates a phone even more precisely. Collecting this data in bulk, which is what the NSA does, effectively puts everyone under physical surveillance.
This is new. Police could always tail a suspect, but now they can tail everyone – suspect or not. And once they’re able to do that, they can perform analyses that weren’t otherwise possible. The Washington Post reported two examples. One, you can look for pairs of phones that move toward each other, turn off for an hour or so, and then turn themselves back on while moving away from each other. In other words, you can look for secret meetings. Two, you can locate specific phones of interest and then look for other phones that move geographically in synch with those phones. In other words, you can look for someone physically tailing someone else. I’m sure there are dozens of other clever analyses you can perform with a database like this. We need more researchers thinking about the possibilities. I can assure you that the world’s intelligence agencies are conducting this research.
When the government patiently reassures you that the data they are collecting is completely worthless and uninteresting, we should become very interested in finding out why they want it and what they are doing with it.