460xThe Air Force took the extraordinary step Thursday of firing nine mid level nuclear commanders and announcing it will discipline dozens of junior officers at a nuclear missile base, responding firmly to an exam-cheating scandal that spanned a far longer period than originally reported. A 10th commander, the senior officer at the base, resigned and will retire from the Air Force. Air Force officials called the discipline unprecedented in the history of America’s intercontinental ballistic missile force. The Associated Press last year revealed a series of security and other problems in the ICBM force, including a failed safety and security inspection at Malmstrom Air Force Base, Mont., where the cheating occurred. More