Have you guys seen this:
Among the weapons the Air Force might deploy are space-based lasers, a space plane capable of delivering a half-ton payload anywhere in the world in 45 minutes, and the "rods from god." The rods are currently just a concept--and have been since the early 1980s--but, if the myriad technical and political hurdles to deployment could be overcome, the system could represent a tremendous leap forward in the military's ability to destroy underground, hardened facilities of the type that have allowed Iran and other rogue states to violate the Nuclear Proliferation Treaty with impunity.
HOW DO THE RODS WORK? The system would likely be comprised of tandem satellites, one serving as a communications platform, the other carrying an indeterminate number of tungsten rods, each up to 20 feet in length and 1 foot in diameter. These rods, which could be dropped on a various targets with as little as 15 minutes notice, would enter the Earth's atmosphere at a speed of 36,000 feet per second--about as fast as a meteor. Upon impact, the rod would be capable of producing all the effects of an earth-penetrating nuclear weapon, without any of the radioactive fallout. This type of weapon relies on kinetic energy, rather than high-explosives, to generate destructive force (as do
smart spears, another weapon system which would rely on tungsten rods, though not space-based).
http://www.weeklystandard.com/Conten...5/700oklkt.asp