Many Americans expressed similar concerns; the poll found that only 9 percent of Internet users are "very confident" that their efforts will protect their privacy. That lack of clarity drives some people to search for new ways to protect their information, while others shrug and conclude that they are powerless.
"What worries you is sometimes you don't know what the scope of it or the scale of it is," said Tarek El-Ghazawi, 55, a computer engineering professor and director of the High Performance Computing Lab at George Washington University's campus in Ashburn. "But you know you are giving up part of your life."
El-Ghazawi, a U.S. citizen who emigrated from Egypt three decades ago and has seen many other societies through his travel for work, said that, by comparison, he trusts that the press, Congress and the courts will help curb the NSA's excesses.
"These are things that are missing in many countries," he said. "I'm not saying that the government is perfect. I'm just saying that the government may be self-correcting over time."
But he does not see similar protections against overreach by private companies. "They are trying to make a quick profit," he said, "and there's not a standard in terms of ethics."
Every time she goes to a CVS, Peggy Brown gets evidence that the drugstore tracks her purchases. The personalized discount offer she is handed with her receipt "shows that they know what medications I've gotten," she said. "And that bothers me more than what the government's doing, because they're doing things to protect us."
But Brown, 59 and a recent retiree from a job in a medical office, figures there is little the average person can do to protect personal data. "Everything just gets more and more exposed," she said.