WASHINGTON -- As the federal government ramps up its around-the-clock struggle against unprecedented cyber intrusions, the civilian and military officials heading those operations are committed to implementing meaningful safeguards to protect citizens' privacy, National Security Agency Director Gen. Keith Alexander said on Tuesday.

Alexander, speaking here at the O'Reilly Media Gov 2.0 Summit, took issue with the notion espoused by many cybersecurity experts that greater security necessarily comes at the expense of personal privacy.

In addition to his role directing the NSA, Alexander also heads up U.S. Cyber Command, a division the Defense Department created earlier this year to protect military information systems and conduct offensive cyberattacks.

"Understandably, citizens of our great nation take a lot of interest in the government's involvement in these areas, as we are people who are guaranteed a level of privacy by our constitution," Alexander said. "As the director of NSA and the commander of U.S. Cyber Command, I have an obligation to the law and to the American people to ensure that everything we do in cyberspace preserves and protects our civil liberties and operates legally under the constitution, while concurrently conducting our mission."

Alexander spoke broadly of the mandate of U.S. Cyber Command, which consolidated existing military information security units, and operates in close partnership with the NSA. In addition to its focus on the .mil domain, Cyber Command is also tasked with providing support to civilian agencies in the information-security arena, particularly the Department of Homeland Security.

He noted that government systems endure more or less constant scrutiny from an array of hackers and other operators at home and abroad probing for vulnerabilities. Defense Department systems, for instance, are subject to roughly 250,000 unauthorized probes every hour, Alexander said.

And the threats are only on the rise. DHS officials last year reported a 150 percent increase in the number of cyber attacks against U.S. systems over 2008.

"Considering the body of both personal and national treasure that resides on the Internet -- information, money, medical records, personal email, critical infrastructure and, most important, national security -- it is not a hyperbole to say that we have as much at risk or more than any other nation," Alexander said.

But in his brief remarks, Alexander devoted the most attention to privacy, echoing the promise he made in his Senate confirmation hearing to balance the demands of national security with a respect for civil liberties.

"Preserving those rights is not an added-on activity or something we do because we have to. It is a core tenant the way we conduct our business all around, cyber included," he said. "That is an obligation that is never compromised."

Kenneth Corbin is an associate editor at InternetNews.com, the news service of Internet.com, the network for technology professionals.

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