Sorry to go off the IS&T trail, but the news that a B-52 was flying around with six unauthorized nuclear weapons made me think fondly (or not so fondly) of my time long ago as an Air Force airborne communications, navigation and electronics warfare technician in Strategic Air Command (SAC).
Say what you will about Gen. Curtis LeMay, he insisted upon and made damn sure that high operating standards were developed, instituted, trained to, and maintained in SAC even after he left - and there was hell to pay if you didn't meet those standards. Maintaining positive control over nuclear weapons was an absolute, non-negotiable; working on an alert bird was always a bit tense as there were these ever present military police with loaded weapons around ready (and I think hoping) to take you out if you violated protocol.
The episode shows how easy it is for risk management even when nuclear weapons are involved to become "routine." The Air Force, of course, says this was an isolated incident ("All evidence seems to point to this being an isolated mistake"), however, it should never have happened. This was supposed to be an "impossible event."
LeMay once supposed said, "I have neither the time nor the inclination to differentiate between the incompetent and the merely unfortunate." In this case, no matter how you slice it, the unfortunate was a matter of incompetence.