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.