During the reign of Hitler, there were several approaches of gaining information on the ‘targeted few’ — e.g., Jews. The Gestapo was their primary ‘tool’ used with physical documents being the key sources (or spying). (Since computers weren’t invented yet.)
Today however, we have Google!! If the federal government wants any information, all they need to do is ask. Just a few years ago you’d need a warrant signed by a judge before you received anything from a tech company. But apparently the rules are changing. The following article discusses Google and what it is doing and how it can affect us. Scary stuff indeed.