Gen. William K. Harrison, Jr., seated at left, and North Korean Gen. Nam Il, seated at right, sign armistice documents in Armistice Hall in Panmunjom, a no man's land between the Koreas, on July 26, 1953.
Employee Sean Tippett works in an operations room at the headquarters of Cisco Systems, a leading provider of Internet network technology, in San Jose, Calif. Experts are debating the need for Internet traceability for security purposes -- and what that would mean for online anonymity and civil liberties in places such as China and Iran.
Defense Secretary Robert Gates delivers the oath of office to Gen. Keith Alexander (right) during the activation ceremony of U.S. Cyber Command at Fort Meade, Md., last month.
Cherie Cullen/AP/Department of Defense
Director of National Intelligence Dennis Blair, seen here in February, offered his resignation Thursday. During the 16 months on the job, Blair struggled to establish his authority over the CIA and other U.S. intelligence agencies.
Manuel Balce Ceneta/AP