LANGLEY AIR FORCE BASE, Va. – The Pentagon for the first time is considering scaling back the massive buildup of drones it has overseen in the past few years, both to save money and to adapt to changing security threats and an increased focus on Asia as the Afghanistan war winds down.

Air Force leaders are saying the military may already have enough unmanned aircraft systems to wage the wars of the future. And the Pentagon’s shift to Asia will require a new mix of drones and other aircraft because countries in that region are better able to detect unmanned versions and shoot them down.

If the Pentagon does slow the huge building and deployment program, which was ordered several years ago by then-Defense Secretary Robert Gates, it won’t affect the CIA drone strikes in Pakistan, Yemen and elsewhere against terror suspects.