How great is thy bounty, metadata?

When documents released by Edward Snowden revealed that the US National Security Agency (NSA) routinely hovers hoovers up metadata on telephone calls made and received in that country, officials first lied about the practice, then defended it on grounds the information obtained was trivial. President Obama insisted the gathering of metadata amounted only to "modest encroachments on privacy" and "a circumscribed, narrow system directed at us being able to protect our people." He emphasized that NSA was "not looking at content." A new, crowdsourced study shows that telephone metadata—information that includes the date, time, and length of phone calls, and the numbers called, but not the...