"On June 5, 2008, Robert Gates announced that he had accepted the resignation of Michael Wynne as Secretary of the Air Force because of "a decline in the Air Force's nuclear mission focus and performance" and "lack of a critical self-assessment culture".Gates specifically cited two incidents in which the Air Force had lost track of nuclear weapons or parts; in one incident, nuclear weapons fuses had been mistakenly sent to Taiwan when helicopter batteries had been ordered, and in the other, the 2007 United States Air Force nuclear weapons incident, a B-52 bomber had been flown across the country armed with six nuclear-armed cruise missiles that no one realized were on board.