In 1998, U.S. Navy ships in the Arabian Sea fired Tomahawk cruise missiles at a number of training camps in Afghanistan where Osama bin Laden was believed to be hiding. The missiles travel at about 550 mph, roughly the same speed as a commercial jetliner. They took more than an hour to reach their targets. If bin Laden had been in one of those camps, he had left by the time the missiles hit.
Such failures have inspired Pentagon planners to examine options that would allow them to strike precisely anywhere in the world in less than an hour, even if no drones, bombers, ships or troops were anywhere near the target. The Pentagon calls the initiative Prompt Global Strike, and in an April interview on Meet the Press, Defense Secretary Robert Gates may have admitted that the U.S. already possessed this capability. “We have, in addition to the nuclear deterrent today, a couple of things we didn’t have in the Soviet days,” he said. In addition to missile defense, he continued, “we have Prompt Global Strike, affording us some conventional alternatives on long-range missiles that we didn’t have before.” The Pentagon answered follow-up questions with silence.
To counter concerns that such an ICBM is heading for Russia, Pentagon officials have said that these weapons could be launched from California, where there are no nuclear-tipped missiles. (Since the placement of ICBMs is regulated by treaty and subject to inspection and verification, this system would, in theory, ensure that Moscow knows whether a missile is armed with a conventional warhead or a nuclear one. But this plan relies on Russia’s trust.)
An alternative to the conventionally armed land-based ICBM is a hypersonic weapon, essentially a cruise missile capable of traveling at many times the speed of sound—faster than anything in today’s conventional arsenal. These missiles would not have to leave the Earth’s atmosphere and would have very different trajectories from ICBMs, so Russia would be less likely to mistake them for nuclear weapons.
The Pentagon has mentioned two non-ICBM candidates for Prompt Global Strike, one from the Army and one from Darpa. Both of these weapons would be boosted into the atmosphere by rockets and then glide back to Earth at hypersonic speeds. In addition to these official Prompt Global Strike options, the Pentagon is conducting at least three other hypersonic or near-hypersonic research efforts: the Air Force’s X-51 WaveRider, which used a scramjet engine to accelerate to Mach 6 in May; the Navy’s Revolutionary Approach to Time-Critical Long-Range Strike project, known as RATTLRS; and the Darpa-sponsored HyFly, a dual-combustion ramjet. (Ramjets and scramjets achieve rocket-like speeds without the heavy burden of liquid oxygen by mixing jet fuel with compressed air that enters the engine from the atmosphere.)
The proliferation of hypersonic research may mean that the Pentagon has faith in the technology. But it also makes black-budget watchers like John Pike, the director of the military information Web site GlobalSecurity.org, suspicious. Pike believes the military’s hypersonic programs may just be a cover for yet another black project. What kind, though, he has no idea.“Have you ever tried to get to the bottom of the American hypersonics program?” Pike asked me rhetorically. “You know, I tried to about five years ago, and it made no sense. There were just too many programs.” Although this could just be typical Pentagon duplication, Pike sees something more suspicious. “If I was building a cover for something, I would either reduce the signal or increase the noise,” he says. “I think they’re increasing the noise.”
Sharon Weinberger is a national-security reporter in Washington, D.C.single page
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