The Cyber Command, headed by Maj. Gen. William Lord, touted on its Web site its capabilities to “secure our nation by employing world-class cyberspace capabilities” and had ambitious plans to have a cyber command presence in all 50 states.

The Cyber Command hyped its capabilities on TV, in Web video advertisements and in a series of high-profile presentations conducted by Lord. The hard sell may have been the undoing of the Cyber Command, which seemed to be a grab by the Air Force to take the lead role in cyberspace. Both the Army and Navy have similar expertise in cyber operations, service sources said.

Philip Coyle, senior adviser with the Center for Defense Information, a security policy research group in Washington, said he believes the Navy’s Network Warfare Command and the Space and Naval Warfare Systems Center have led the way in cyberspace. The Army engages in cyberspace operations daily in Afghanistan and Iraq, said Coyle, who served as assistant secretary of Defense and director of its operational test and evaluation office from 1994 to 2001.

The decision to ratchet back the Cyber Command may have come from Adm. Mike Mullen, chairman of the Joint Chiefs of Staff, who wants to see a greater role for the Navy in cyberspace, said an Air Force source. Coyle speculated that the Air Force may have been too public in pushing the Cyber Command and is now suffering from its own hubris.

Other services also have cyberspace capabilities and the National Security Agency has taken an active role in cyber operations, including a broad, and controversial, wiretapping program.