For the public source of this information, rewind to 2013: https://www.washingtonpost.com/investigations/us-intelligence-mining-data-from-nine-us-internet-comp

For the public source of this information, rewind to 2013: https://www.washingtonpost.com/investigations/us-intelligence-mining-data-from-nine-us-internet-companies-in-broad-secret-program/2013/06/06/3a0c0da8-cebf-11e2-8845-d970ccb04497_story.html https://www.washingtonpost.com/investigations/us-intelligenc... https://cryptome.org/2014/01/nsa-prism-dk.pdf https://cryptome.org/2014/01/nsa-prism-dk.pdf You have to put together what we know about PRISM with recent testimony. https://en.wikipedia.org/wiki/Jewel_v._NSA https://en.wikipedia.org/wiki/Jewel_v._NSA is extremely important here. The NSA argues it can collect virtually every scrap of data flowing across US communications systems and that it does not violate your rights because as long as no one is looking at it your 4th amendment rights aren't violated. So to "look" at the data they get a secret FISA warrant. Jewel was defeated in court with the same tired argument of Clapper et. al -- "Your facts are inaccurate, but we won't tell you how because it is a state secret. Case dismissed. You let us worry about protecting your privacy within our walled garden." NSA directors have a long history dating back to 2002 with Hayden of misleading congress and then saying "oops, sorry about that." It is a naked power game between congress and the executive branch and a bit of political chicken because the intelligence committees can only go so far before the president/white house can say the legislative branch is undermining your freedom and aren't tough on terror.... which will not go well for anyone at reelection time if it sticks. The back and forth goes on. The picture painted, and I can't dig everything up is that, essentially, the NSA collects almost everything that happens on US soil. It has a legal fiction via executive orders (see Snowden emails) that let it do this. And then if searches of this data turn up anything interesting (since automated computer searches don't require a warrant under this legal fiction) they then apply for a secret FISA warrant and then humans can "look" at the collected data. And since no humans were collecting or looking at your data your 4A rights are fine and safe. edit: I guess I meant to add this legal construction is why the "how" of their collection matters so much. Until we have accurate details of the "how" we can't even begin to argue against them in open court. And since the executive branch tries its very best to keep the "how" secret (for many not obvious reasons!) these things are important. I have seen people dismiss the importance of the technical details as just bits and bytes and what matters is the politics at play, but the "how" is very important as shown by the failure of Jewel to win in court due to specious "state secrets" arguments.