That document states that PRISM is "an internal government computer system used to facilitate the government's statutorily authorized collection of foreign intelligence information from electronic communication services providers under court supervision" and that the government isn't going directly into the servers of these companies.
The intelligence-gathering is "not used to intentionally target any U.S. citizen, or any other U.S. person," the document says. Rather it's aimed at a "foreign target" to gain information about "terrorism, hostile cyber activities, or nuclear proliferation."
"Targeting procedures are designed to ensure that an acquisition targets non-U.S. persons reasonably believed to be outside the United States for specific purposes, and also that it does not intentionally acquire a communication when all the parties are known to be inside the U.S." the document says.
The Guardian published yet more revelations about the NSA yesterday, with Glenn Greenwald and Ewen MacAskill's story on a NSA data-mining tool called "Boundless Informant" that details and maps by country the data collected by the NSA from telecommunications and social-networking sites plus more.
The Guardian article said the NSA tool collected almost 3 billion pieces of intelligence from U.S. computer networks over a 30-day period ending in March. The Mideast, Egypt and India were targets of much data collection, according to the Guardian.
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