A look at nuclear force security lapses revealed so far

The Associated Press has uncovered a series of security lapses and other troubles in the nation's nuclear forces. On Thursday, the Air Force announced it fired nine nuclear commanders, allowed a colonel at the base to resign, and would discipline dozens of junior officers as well as a series of new or expanded programs to deal with problems of leadership and base facilities.

Key missteps by personnel who handle the world's most deadly weapons and the military's response:

— Nineteen missile crew members in the 91st Missile Wing at Minot Air Force Base, N.D., are temporarily taken off duty last spring and given weeks of remedial training after being found unfit to perform. The wing's deputy commander of operations complains of "rot" in the force. The officer in charge of crew training and proficiency is fired.

— The 341st Missile Wing at Malmstrom Air Force Base, Mont., fails a safety and security inspection. Nine days later the officer in charge of security forces there is relieved of duty. The unit passes a do-over.

— Twice the Air Force punishes officers involved in separate incidents of opening the blast door of their launch control center while one of the two launch officers was asleep, in violation of Air Force rules.

— Key members of the Air Force's nuclear missile force are feeling "burnout" from what they see as exhausting, unrewarding and stressful work. The finding, in an unpublished draft of a RAND Corp. study provided to the AP, also cites heightened levels of misconduct such as spousal abuse and says court-martial rates in the nuclear missile force in 2011 and 2012 were more than twice as high as in the overall Air Force. The courts-martial rate in 2013 declines but still is higher than the overall Air Force.

— The Air Force removes Maj. Gen. Michael Carey from command of the 20th Air Force, which is responsible for the entire Minuteman 3 missile force, for embarrassing, drunken behavior at meetings in Russia and spending time with "suspect" women. This happens two days after a Navy admiral, who was second-in-command at the military's main nuclear war-fighting command, is relieved of duty amid a gambling-related investigation. Carey is allowed to remain in the Air Force as a staff officer at Air Force Space Command.

— At least 34 nuclear missile launch officers are implicated in a cheating scandal and are stripped of their certification in what the Air Force believes is the largest such breach of integrity in the nuclear force. The cheating involves the monthly test on their knowledge of how to operate the missiles. That scandal is revealed as part of a drug-use investigation that involves three ICBM launch officers.

— Defense Secretary Chuck Hagel orders an independent review of the nuclear force and summons the most senior Pentagon leaders to discuss its serious missteps, leadership lapses and personnel problems.

— Air Force documents show that failings among missile launch crews at Minot during a March 2013 inspection were worse than originally reported. The documents also hint that Minot had the makings of a possible exam-cheating problem many months before a cheating scandal erupted at the 341st Missile Wing in Montana.

— The Air Forces fires nine midlevel nuclear commanders, allows a colonel to resign, and says it will discipline dozens of junior officers at Malmstrom Air Force Base in response to the exam-cheating scandal. Investigators determine that the cheating began as early as November 2011 and continued until November 2013. The Air Force also announces a series of new or expanded programs to improve leadership development, to modernize the three ICBM bases and to reinforce "core values" including integrity.