The four-star generals prepared for the event with a day of meetings last month at U.S. Cyber Command and the National Security Agency, where they and some three-star generals were briefed on the rapidly changing nature of the cyber threat and U.S. capabilities.

Major General Earl Matthews told the Air Force Association conference last month that a high-level meeting was needed because "not all four stars can talk as eloquently about cyber as they can about air and space power."

Defense Secretary Leon Panetta last week warned that foreign actors were targeting U.S. computer systems that control chemical, electricity and water plant, as well as those that guide the nation's critical transportation networks.

He said the U.S. military could act pre-emptively if it detects an imminent threat of cyber attack.

U.S. military officials have been more outspoken in recent months about U.S. efforts to develop offensive cyber weapons, but few details have emerged.

At next month's meeting at Andrews Air Force Base outside Washington, the Air Force's top brass will discuss the service's current mission and cyber capabilities, future staffing and funding needs, and how to organize the work.

Lieutenant General Michael Basla, who became the Air Force's chief information officer in June, has said the gathering will be used to "articulate the Air Force's cyberspace vision" and lay the groundwork to accomplish that vision.

Matthews said cyber threats and capabilities have resulted in a significant shift in the Air Force, akin to the introduction of aircraft over a century ago, and innovative cyber technologies would be a game-changer in future conflicts.

General Mark Welsh, the Air Force's new chief of staff, last month told reporters that he planned to restrain spending for cyber operations until the Pentagon more clearly spelled out its requirements for new "cyber warriors."

(Reporting By Andrea Shalal-Esa; Editing by Mohammad Zargham)

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