"Every time I write an email," he said, "I have to decide if I want Obama to read it, or if I want Putin to read it."

It may be hyperbolic to suggest that world leaders personally comb through individual email accounts, but the reporter's point stands: When you use services like Gmail, Mail.ru, Facebook, Dropbox, Slack, or any other site that stores your data, they will hand your private information to governments when compelled to do so and in some cases, merely when asked. Last year, the Supreme Court ruled that the government usually needs a warrant to access private data held by third-party companies. But even with new legal protection, email remains all too easy for governments to quietly obtain. Many companies, like Facebook, have shared personal information even more widely, with private entities.