"The Air Force wants to upgrade its aging nuclear missiles and the hundreds of underground silos that hold them," says Beckhusen. "One idea it’s exploring: the construction of a sprawling network of underground subway tunnels to shuttle the missiles around like a mobile doomsday train. As one does."
"As first reported by Inside Defense, the Air Force Nuclear Weapons Center will award several study contracts next month worth up to $3 million each to research the idea. A broad agency announcement from the Air Force describes the hair-raising concept, intended to keep the weapons secure through 2075, as a system of tunnels where nuclear missiles are shuttled around on rails or some undefined 'trackless' system."
"The project would likely be gigantic, expensive and take decades to build — all things that cut against cut against these relatively lean times at the Pentagon," cautions Beckhusen. But other options for replacing the U.S.’ silo-launched nuclear arsenal of 420 Minuteman III ballistic missiles seem equally costly and complex.