Rods from God

Michael Goldfarb, in the Daily Standard, has a fascinating column about a potential kinetic energy weapon he calls "Rods from God":

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 target 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).

The column is well worth reading, both for the technical details and for the political implications.

As I think about the implications of such a weapon myself, my conclusion is that it would be an almost ideal way for a (the) superpower to project power. Near-instantaneous deployment, nuclear-level power but non-nuclear, very expensive and very high-tech (thus putting it out of reach of terrorists and all but a few countries), unmanned (so no soldiers need go in harm's way), and infinitely extendable. It seems to me that (as with many weapons systems) the bulk of the investment is in up-front research and development; scaling it up would be much less expensive than developing it. Also, unlike a nuclear weapon, this not something that could be sold or otherwise tranferred to a terrorist or a rogue state — the infrastructure required to support it is substantial.

The main question I have is this: when can we have one?