While leading tech CEOs called on Congress to rein in the National Security Agency, one prominent Silicon Valley figure Thursday turned his ire toward a different target, calling former NSA contractor Edward Snowden a "traitor" for leaking government secrets.

"Obviously he's a traitor. ... He stole national security secrets and gave them to everybody on the planet," venture capitalist Marc Andreessen said in an interview with CNBC, while also blasting the Obama administration for not doing more to counter the Snowden leaks.

Andreessen conceded his view of Snowden isn't shared by many in Silicon Valley. But his comments and the tech leaders' call for tougher reforms illustrate how raw the NSA spying issue remains in Silicon Valley -- exactly one year after the first of many news reports appeared that were based on Snowden's leaks about agency efforts to collect phone records and Internet user data.

Top executives at Google, Facebook and other leading Internet companies have previously voiced outrage over programs revealed by those leaks, including NSA efforts to weaken encryption and intercept transmissions between the companies' overseas data centers. This week, the CEOs of nine leading companies published an open letter in several newspapers, urging the U.S. Senate to adopt tougher reforms than those contained in the so-called USA Freedom bill passed by the House of Representatives last month.

While the companies have beefed up security to guard users' data, "the government needs to do more," said the letter signed by Google's Larry Page, Facebook's Mark Zuckerberg and other top CEOs.

The same companies have complained that the NSA revelations will harm their business, which depends on users trusting them with often-sensitive information. The leaks are already having an economic impact, said Dean Garfield of the Information Technology Industry Council, which represents many of the companies, in testimony Thursday at a Senate Intelligence Committee hearing.

Sen. Dianne Feinstein, the California Democrat who chairs the committee, has previously defended the NSA. But she said Thursday that she is open to tightening language in the House bill that tech companies and civil liberties groups have described as a potential loophole for continued bulk collection of Internet user data.

Despite the economic fallout, many in the tech industry see Snowden's actions as heroic. He was warmly received by an audience of tech professionals when he spoke, by video connection from Moscow, at the South by Southwest conference in Austin earlier this year. They applauded when Snowden's attorney read a message from Tim Berners-Lee, a respected computer scientist and Internet pioneer, who wrote that Snowden's leaks were "profoundly in the public interest."

While Snowden's defenders, including the American Civil Liberties Union, view his actions as those of a legitimate whistle-blower, Andreessen disagreed. The co-founder of Netscape, an early Web browser firm, he now leads the prominent tech venture firm Andreessen Horowitz and sits on the boards of Facebook, eBay and Hewlett-Packard.

Speaking on CNBC, Andreessen echoed earlier statements in which he said he wasn't surprised by the NSA spying. "I just thought that's what they were doing," he added. "I thought everybody knew that."

At the same time, Andreesseen said the revelations have "very serious and very worrying" implications for the ability of U.S. tech companies to sell their products overseas. He said foreign governments may use the leaks as an excuse to impose trade barriers against U.S. tech products.

Andreessen also accused President Barack Obama of having "no plan ... no strategy" for dealing with the leaks. "The Snowden reveals just keep coming out. The administration is just letting the NSA hang out to dry. I think they're letting the American tech industry hang out to dry."

His comments drew criticism on Twitter, where Andreessen noted in a series of posts that he has long supported strong encryption. When asked by Dan Gillmor, a longtime tech writer and academic, if he was bothered by the NSA hacking into U.S. companies' networks, Andreessen responded by tweeting: "That part doesn't thrill me." He later added, "I'm not saying surveillance of U.S. citizens is right."

Andreesseen argued that most of the spy programs revealed by Snowden are directed at foreign targets, although civil liberties experts say data from many Americans was also collected.

"The comprehensive leaking of U.S. intelligence operations globally are treasonous by definition," Andreessen wrote on Twitter. Still, he acknowledged to CNBC that he's in "a distinct minority" in calling Snowden a traitor. "I think most people in Silicon Valley would pick the other designation."

Contact Brandon Bailey at 408-920-5022; follow him at Twitter.com/BrandonBailey.