"Granted there is something inherently creepy about Uncle Sam scooping up so much information about us," Mr. Boot wrote. "But Google, Facebook, Amazon, Twitter, Citibank and other companies know at least as much about us, because they use very similar data-mining programs to track our online movements. They gather that information in order to sell us products, and no one seems to be overly alarmed. The NSA is gathering that information to keep us safe from terrorist attackers. Yet somehow its actions have become a 'scandal,' to use a term now loosely being tossed around."