Because the intelligence community has interpreted it to allow them to collect enormous amounts of U.S. persons communications and have analysts parse it and re

Because the intelligence community has interpreted it to allow them to collect enormous amounts of U.S. persons communications and have analysts parse it and read it to make a determination on its foreign intelligence relevance. Or if you're hot, some teenage intelligence analyst will make a copy of that nude you sent to your spouse to save for his personal spank bank. It's all for national security you see. All without a warrant. Because intentionally collecting information they know will be predominantly on U.S. persons is a-okay as long as one or two drops in that ocean of U.S. persons communication is of foreign nationals communicating.