In a 2011 poll by The Associated Press and the NORC Center for Public Affairs Research, 54 percent of those surveyed felt protecting citizens' rights and freedoms should be a higher priority for the government than keeping people safe from terrorists. At the same time, 64 percent said it was sometimes necessary to sacrifice some rights and freedoms to fight terrorism.
"Whenever something like 9/11 happens, it does tend to cause people to change their minds," Richards said. "But I think what's interesting is it has to be a long-term conversation. We can't, whenever we're scared, change the rules forever."
But up until now, there's been only limited debate about where and how to redraw the lines on surveillance. At the same time, explosive growth in social networking, online commerce, smart-phone technology, and data harvesting for targeted marketing have introduced many Americans to all sorts of rich new experiences and conveniences. People have become enamored with the newest technology and media without giving hard thought to the risks or tradeoffs, experts say.
"This ... has really dulled our sense of what privacy is, why it's important," Parenti said. "The fact of the matter is that millions of people are actively participating in keeping dossiers on themselves."
It can, at first glance, seem a leap to draw a line between the way we share our private lives on Facebook or our search habits with Google and concerns about government surveillance. But surrendering privacy, whether to business or government, fundamentally shifts the balance of power from the watched to the watchers, experts say.
Americans may have largely accepted the idea of sharing personal information with businesses or in open forums as the necessary tradeoff for the use of new technologies. But they have done so without stopping to consider what those businesses are doing with it or how police or security officials might tap into it.
"We've allowed surveillance of all kinds to be normalized, domesticated, such that we frequently fail to tell the difference between harmful and helpful surveillance," said David Lyon, director of the Surveillance Studies Centre at Queen's University in Kingston, Ontario. "And we assume all too easily that if it's high tech, it's better."
In interviews in recent days, many people described a growing sense of unease about the trade-offs between privacy, technology and the desire for safety.
In Chicago, Joey Leonard, a clerk at the Board of Trade, sat outside at lunch hour checking apps on his smart phone and ruminated about the government's actions. Leonard, a recent college graduate, noted that he was just 11 at the time of the 2001 terrorist attacks. He approved of the heightened security measures to prevent a recurrence. But he said it has also becomes clear that terrorists will act even if the government is watching, raising questions about the tradeoffs.
"Society is changing and technology is changing. I understand there are threats but I do think this is a little too much," Leonard said. "The government is trying to control everything. I feel like I'm being watched 24/7. ... It's like they're trying to get their fingers in every aspect of your life and I don't think it's helping."
In Salt Lake City, Utah, truck driver Elijah Stefoglo hadn't heard about the NSA's program, but said everyday interactions with technology give him plenty to consider. Stefoglo, who lives in Minneapolis, pointed out that most newer rigs come equipped with GPS tracking and even camera systems, technology he worries could be abused. At the same time, he noted, many states are fitting driver's licenses with computer chips to track and store data, posing yet another threat to privacy.
Expectations of privacy have slowly evolved, and younger people are growing up with a different standard, he said.
"They're trying to put it in their heads that it's normal. You have to do this. This is for your security. If you do this, you're going to be safer," he said. "In what way? Criminals are still going to do whatever they want."
- 23 of the best Shakespearean insults to...
- More than 2,500 confirmed dead in Nepal...
- Mitt Romney to Jacksonville University...
- Former Romney finance chairman courting a...
- Photos: Celebrating 25 years of spectacular...
- How to help Nepal earthquake victims
- Utah construction companies fined, ordered to...
- Ceremonies mark liberation of concentration...
- Former Romney finance chairman courting... 56
- Gay marriage a difficult issue for GOP... 30
- Obama sounds alarm on climate damage in... 29
- House Benghazi panel calls Clinton to... 29
- Yellowstone supervolcano is super big,... 24
- American, Italian hostages killed in US... 22
- Hatch, Lee split on new attorney general 13
- What could McDonald's do to fix its... 11