On August 29-30, 2007, six AGM-129 cruise missiles armed with W80-1 thermonuclear warheads were loaded onto a B-52H bomber at Minot Air Force Base. The aircraft flew them to Barksdale Air Force Base in Louisiana. The flight crew did not know the missiles were nuclear-armed. Total time the warheads were unaccounted for in the nuclear command chain: 36 hours. Each W80-1 warhead has the explosive yield of approximately ten Hiroshima bombs. The Secr…