versus its contribution to defense effectiveness. Specifically, the justification provided to the committee for developing this new space-based sensor system was questionable, and the committee’s analysis shows that its objective can be better accomplished by deployment of forward-based X-band radars based on the Army Navy/transportable radar surveillance model 2 (AN/TPY-2) system design at much lower total-life-cycle cost.

•   The AN/TPY-2 radar already developed for THAAD and already deployed can be exploited to provide the required capabilities for all foreseeable defense missions.

•   Taking advantage of the existing manufacturing base and the learning curve as more units are built would be a very cost-effective way of supporting the recommendations in this report.

Major Recommendations

The committee’s major recommendations are divided into two groups: (1) boost-phase systems and (2) non-boost-phase systems.

Boost-Phase Systems

Major Recommendation 1: The Department of Defense should not invest any more money or resources in systems for boost-phase missile defense. Boost-phase missile defense is not practical or cost-effective under real-world conditions for the foreseeable future.

•   All boost-phase intercept (BPI) systems suffer from severe reach-versus-time-available constraints. This is true for kinetic kill interceptors launched from Earth’s surface, from airborne platforms, or from space. It is also true for a directed-energy (laser) weapon in the form of the airborne laser (ABL), where reach is limited by problems of propagating enough beam over long distances in the atmosphere and focusing it onto a small spot, even with full use of sophisticated adaptive optical techniques.

•   While there may be special cases of a small country such as North Korea launching relatively slow burning liquid-propellant ICBMs in which some boost-phase intercepts are possible, the required basing locations for interceptors are not likely to be politically acceptable.13 This recommendation is not intended to preclude funding of generic research and development such as the ABL test


13For example, while a North Korean ICBM aimed at Hawaii and some other Pacific locations could be intercepted in boost phase by a properly located Aegis ship, the United States cannot realistically or prudently expect that BPIs intended for defense against North Korean or Iranian attacks can be stationed in Russian or Chinese airspace or over other nonallied territory (or where overflights of such territory would be necessary to reach on-station locations), at least short of a full resolution of Russian and Chinese concerns about U.S. missile defense and agreement on extensive cooperation in such defense.

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