"We've entered a new technological era, the era of big data," Whitehouse said. "Our intelligence establishment is not the only group that's playing in this big data area."
Others at the hearing called for more transparency and oversight of NSA surveillance. Surveillance reforms are needed because the rest of the world is losing trust in U.S. technology companies, said Edward Black, president and CEO of the Computer and Communications Industry Association.
Continued surveillance of U.S. services will drive Internet users to foreign alternatives, Black said. "We should not take for granted decades of progress in creating security and fostering user trust," he said. "And we should not discount how easily that foundation can be damaged."
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