Richard Garwin and Theodore Postol have proposed systems that would intercept ICBMs in their boost phase. In contrast with other boost-phase proposals, theirs are not adaptations of existing missile-defense systems but rather systems designed and built expressly for the purpose of boost-phase NMD.
Garwin describes the technical details of a possible system. Missile launches would be detected by the existing Defense Support Program (DSP) satellites, which would also provide initial trajectory information. A computer system would relay that information to the interceptor site, based on land or on a military cargo ship, 60-70 seconds after ignition of the ICBM, resulting in interceptor launch roughly 100 seconds after ICBM ignition. The interceptor would use a three-stage booster similar to that of the Clinton midcourse system, reaching an ultimate velocity of 7 km/s in 100 seconds. It would be self-guided, homing in on the missile booster’s flame after clearing the atmosphere. Its main sensor would target visible light, and thus not require cooling, in contrast with that of the Ground Based Interceptor. When the kill vehicle came close to the missile, it would use a secondary thermal-infrared detector to find the missile body. This detector would be require only a limited field of view and would thus be quite simple. The seeker would be supported at its center of mass in order to operate in a high-acceleration environment. Assuming a kill vehicle of 100 pounds, its collision with the missile would result in the equivalent of detonation of about 1000 pounds of high explosive, damaging or destroying the rocket. If the booster uses multiple engines in a ring configuration and some of the engines are damaged or destroyed while others are not, the missile could divert hundreds or even thousands of miles from its planned course. Warhead impact, and possible detonation, could occur anywhere in a wide area and be impossible to predict.
Various proposals exist for the stationing of boost-phase launch platforms. In all proposals, interceptors are stationed in such in a way that only allows them to defend against the rogue state of concern, rather than against Russia or China. In the case of North Korea, either a joint US-Russian site south of Vladivostok or a sea-based platform in the Japan Basin would be appropriate. While the sea-based platform would give greater American control over the system, the ground-based solution would likely be far more survivable, since hardened silos could be used for interceptor storage.
For defense against Iraq, a site in southeastern Turkey would be best. To defend against Iran, a much larger country, interceptors would have to be stationed in both the Gulf of Oman and in the Caspian Sea. Using the Caspian Sea might prove to be politically challenging, as access is controlled by Russia.
While the system described above might be incorporated within a modified ABM treaty, there are other obstacles to Russian cooperation. Most importantly, Russia is not currently an adversary of North Korea; participation in building defenses specifically targeted at North Korean missiles would change that.
Cost estimates have not been made for these systems. The administration's FY02 Budget Estimate devotes 50 million to basic research in alternative sea-based boost phase systems.
Maintained by Michael Levi