(Image: Listening in via Shutterstock)Washington – The American people are growing increasingly concerned about reports of domestic spying. And Congress isn’t sure how to respond.

The public’s views have been evolving over the past week and a half. When news broke earlier this month that the National Security Agency could tap data from phone and Internet companies, most people accepted the tradeoff between security and privacy. Members of Congress routinely defended the programs.

Not anymore. By week’s end, polls suggested a groundswell of concern and lawmakers were hearing from constituents. Conversations at the Capitol had a new hue: Sure, the government says it has safeguards in place so it won’t listen to my calls and read my emails – but can it ever really control some rogue operator? And where is all that data? Who’s in charge?

The politicians are in a fix. Administration officials have secret briefings and most lawmakers walk out tight-lipped, skittish about revealing any details or betraying any doubts.

Rep. C.A. Dutch Ruppersberger of Maryland, the top Democrat on the House Intelligence Committee, defends the programs but concedes the rising concerns are “an education issue.” And, he laments, “Our hands are always tied on intelligence because we can’t say a lot of things we’d like to.”

Evidence of lawmakers responding to the mounting public concern keeps surfacing. Committee hearings called for other purposes became dominated by tough questioning of administration officials about spying. House of Representatives members emerged from a high-level briefing questioning whether oversight was adequate. Senators from both parties, including Dianne Feinstein, D-Calif., the chairman of the Senate intelligence committee, pledged a fresh look at the programs.

“Initially people were going, ‘That’s interesting, I wonder what this is about.’ They were reserving judgment,” said Sen. Mike Johanns, R-Neb. “As they’re learning more and more about it they’re less likely to reserve judgment.”

It’s still unlikely Congress will make radical changes to the programs, one of which examines cellphone records and one which allows the government access to the online activity of users at nine Internet companies

The key to any major change rests with congressional leadership, which largely controls the agenda in Congress. Action seems unlikely.

“I’ve made it very clear this program does not target innocent Americans in any way, shape or form,” said House Speaker John Boehner, R-Ohio. “These programs have helped keep America safe.”

Since the revelations surfaced, the mantra among congressional leaders and congressional national security experts is that none of the news should come as a shock. If the public only knew what they did, they’d understand. Intelligence committees insist they’ve worked hard to keep an eye on the programs – a claim difficult to verify – and say lawmakers have long been free to raise questions.

“I’m not on the intelligence committee. I’ve never felt like I’ve been shut out of the process,” said Sen. Lindsey Graham, R-S.C. “Any member of Congress who’s astonished by this program has nobody to blame but themselves. It was there to be learned about.”

Yet Congress is driven by its political needs. And polls show a shift in opinion, and often the confusion Americans have about the programs.

A CBS News survey taken Sunday and Monday found 36 percent thought the government had gone too far in infringing on people’s privacy, 13 percent said it had not gone far enough, and 46 percent said the balance was about right.

The poll also asked people if they approve of government agencies collecting phone records from ordinary people “in order to reduce the threat of terrorism.” Fifty-eight percent disapproved, while 38 percent approved.

Such numbers prod politicians to probe. When FBI Director Robert Mueller appeared Thursday before the House Judiciary Committee to discuss bureau operations, he wound up in lengthy exchanges over the programs.

A day earlier, Gen. Keith Alexander, the director of the National Security Agency, went to the Senate Appropriations Committee for a budget hearing. Instead, he patiently explained the government’s strict guidelines governing domestic surveillance. Many senators weren’t satisfied.

“If you knew that a suspect had made a call into area code 312, the city of Chicago, it certainly defies logic that you’d need to collect all of the telephone calls made in the 312 area code on the chance that one of those persons might be on the other end of the phone,” said Senate Majority Whip Richard Durbin, D-Ill.

For all the escalating angst, any change likely would come gradually if at all. A bipartisan group of eight senators has proposed adding some transparency to the secret court that approves spying, an effort that has picked up little steam.

Feinstein said her committee would assess “what’s come out.” Serious moves also were afoot to try to declassify more material, or at least subject the programs to more scrutiny.

Whether the drumbeat for change will grow next week probably depends on what lawmakers learn as they talk to constituents back home this weekend.

Rep. Ted Deutch, D-Fla., a House Judiciary Committee member, sent a message to his South Florida constituents Thursday asking for their views. Hundreds have called or written Deutch’s offices this week with a variety of concerns, seeking details about the programs, insisting they’re valuable tools against terrorism and so on.

Rep. Pat Tiberi, R-Ohio, also found an uptick in calls and emails, and echoed the thoughts of many colleagues.

“There’s a lot of misinformation out there. That gives people additional angst,” he said. “We need to explain this to people.”

And then see what people want.