(CNN) -- As the story about the National Security Agency surveillance continued to unfold last week, some of President Obama's supporters, as well as some of his Republican critics, were quick to jump to his defense. Chairman of the House of Representatives Intelligence Committee Mike Rogers warned that the allegations about the NSA were wrong. "They are seeing three or four pieces of a thousand-piece puzzle and trying to come to a conclusion." Speaking before a congressional committee, Director of National Intelligence James Clapper said the monitoring of calls by 35 world leaders was just about spying, something that every country did and so there was nothing to be worked up about. "Some of this reminds me of the classic movie 'Casablanca': 'My God, there's gambling going on here,'" Clapper said.
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Some officials dismiss the impact of NSA revelations, saying every country spies
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Julian Zelizer: It's dangerous to ignore the risk that spying will become too intrusive
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In the 1960s, 1970s, activists were illegally targeted by government agencies in the U.S.
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Zelizer: It's crucial to set limits for government agencies such as NSA
In the long run, such steps would have the potential to strengthen trust and confidence in the NSA, and allow it to do the work that is needed to secure the nation and our allies against the threats the @placeholder continually faces.