Research also shows that closely watched prisoners’ sense of perpetually being watched contributes to anxiety, an inability to form bonds, and loss of individual initiative. In authoritarian regimes such as China and Iran, dissidents speak compellingly of the trauma and despair they endure as a result of being followed, monitored, and tracked in a dossier. Scarcely a week ago, the United States announced the easing of sanctions on Iran to permit the flow of technologies and tools to enable Iranians to be “more able to protect themselves against government hackers.” The rationale seemed obvious.

The few studies that have looked at the effects of similar tactics in less hostile and restrictive settings have confirmed similar, though more muted, effects. An EU privacy study documented that under surveillance, individuals make choices that are more likely to conform to mainstream expectations. A Finnish research project installed cameras and recording devices in the homes of 12 families and documented annoyance, concern, anxiety, and anger among the watched, as well as a loss of spontaneity as inhabitants contemplated any new social event or activity being captured by the cameras.

Now multiply that 12 by 100 million and there are grounds for concern about how surveillance may reshape Americans’ moods, psychology, and social life on a national scale. Until now, it might have been argued that what we did not know — or chose to ignore — about the staggering breadth of government surveillance couldn’t hurt us. Now that it’s front page news and trending on Twitter, that’s no longer true. The idea that friendly and trusted online brands — Yahoo, Facebook, and others — had some part in enabling the NSA’s broad incursions raises questions of what platforms and transactions, if any, can be fully trusted.