For the first time, NSA chief and head of the U.S. Cyber Command Gen. Keith Alexander admitted America is ready to attack in cyberspace. Never before has a U.S. official acknowledged that the U.S. government is working on or is in possession of malware capable of attacking a foreign nation in a cyber conflict, despite the fact that at least one attack — the famous Stuxnext worm — has been attributed to the U.S.

On Wednesday, in his annual testimony to the House Armed Services Committee, Alexander took the cyberwar rethoric coming out of Washington up a notch. "I would like to be clear that this team, this defend-the-nation team, is not a defensive team," he said. "This is an offensive team." In other words, this cyber army is ready to retaliate in case of a cyber attack against the United States.

As part of the expansion of the cyber security force, Alexander also said that he is adding 40 teams, 13 focused on offensive operations and 27 for surveillance and training. Thanks to the expansion, the cyber command will grow from 900 to a corps of more than 4,000 employees.

As previously reported, the new command will have three arms: two defensive ones that will secure critical infrastructure and the Pentagon's own system, and an offensive one. This expansion, Alexander explained, is justified by the imminent threat of a cyber attack on U.S. critical infrastructure, like its power grid or the financial system. According to Alexander, this kind of attack poses a major threat, even bigger than a terrorist attack.

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James R. Clapper, the director of national intelligence, who also testified yesterday, said that such an attack "would result in long-term, wide-scale disruption of services, such as a regional power outage." Although he admitted that there is only a "remote chance" of a "devastating" attack within the next two years.

In a statement that's bound to put privacy and Internet freedom advocates on red alert, Alexander said that the best way to prevent or prepare for a cyber attack is to monitor online traffic through Internet Service Providers, which would then notify the U.S. government of any threat.

Clapper also complained during the hearing that he was forced to testify about these things. "An open hearing on intelligence matters is something of a contradiction in terms," he said.

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