What I'm fundamentally getting at in my OP is elite deviance:
The NSA will not protect us from the deviance of those with real power, because those with real power can fight back. Those with real power are also those who have the resources to execute a real worst-case-scenario attack-- exactly the kind of terrorist attack this is supposed to be protecting us from. If somebody nukes New York it will not be an anti-government windbag with an Internet connection who just got fired from their job and decided to search for "how to build an atomic bomb." It will be an elite deviant, supported by a network of elite deviants and powerful ideological sympathizers. Someone with the motive and the means to execute on such a thing.
This system might detect motive with some probability of success, but it will not be used against those with means because those people (and their supporters) will pull strings and hire million dollar attorneys. (Or turn agents, pay off managers at government contractors, etc.)
I also have serious doubts about whether it'll stop the next Boston bomber or Timothy McVeigh either, but for different reasons: small players easily vanish into an ocean of false positives. There are mathematical limits that come into play here-- it's why undirected fishing expeditions in seas of scientific data are rarely successful.
This project is a dangerous, politically and socially irresponsible pork-barrel boondoggle that creates far more opportunities for crime and corruption than it prevents. Limits to government power and requirements for judicial oversight (a.k.a. peer review) aren't arbitrary whims or kooky notions supported by paranoids. They're a lot like the OSHA rules put in place at factories and industrial facilities. They are there to keep people from getting hurt and to keep expensive, dangerous accidents from taking place.
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