How Did the C.I.A. Lose a Nuclear Device in the Himalayas? The mission demanded the utmost secrecy. A team of American climbers, handpicked by the C.I.A. for their mountaineering skills — and their willingness to keep their mouths shut — were fighting their way up one of the highest mountains in the Himalayas. Step by step, they trudged up the razor-toothed ridge, the wind slamming their faces, their crampons clinging precariously to the ice. One misplaced foot, one careless slip, and it was a 2,000-foot drop, straight down. Just below the peak, the Americans and their Indian comrades got everything ready: the antenna, the cables and, most crucially, the SNAP-19C, a portable generator designed in a top-secret lab and powered by radioactive fuel, similar to the ones used for deep sea and outer space exploration. Antenna Radioactive material inside Transceiver Portable nuclear device SNAP-19C The plan was to spy on China, which had just detonated an atomic bomb. Stunned, the C.I.A....