potential North Korean threat. Moreover, the current GBIs are very expensive per round when compared to missiles of similar complexity at the same point in their development and has limited ability to defend the eastern United States against threats from the Middle East.

Consequently, the committee believes that a properly designed midcourse defense is the most versatile and cost-effective way to provide a resilient limited defense of the United States. Specifically, the committee finds as follows:


1.   The GMD system lacks fundamental features long known to maximize the effectiveness of a midcourse hit-to-kill defense capability against even limited threats. They could, however, readily be incorporated as part of the recommended GMD-E described in this chapter. The cost-effectiveness of various alternatives shown in Chapter 4 suggests that a substantially lower overall cost could be achieved through an evolution that is detailed in this chapter.

2.   Discriminating between actual warheads and lightweight countermeasures has been a contentious issue for midcourse defense for more than 40 years (see classified Appendix J for greater detail). Based on the information presented to it by the Missile Defense Agency (MDA), the committee learned very little that would help resolve the discrimination issue in the presence of sophisticated countermeasures. In fact, the committee had to seek out people who had put together experiments like the midcourse space experiment (MSX) and High-Altitude Observatory 2 (HALO-2) and who had understood and analyzed the data gathered. Their funding was terminated several years ago, ostensibly for budget reasons, and their expertise was lost. When the committee asked MDA to provide real signature data from all flight tests, MDA did not appear to know where to find them. MDA showed the committee summaries of results without the data to support them. It appeared to the committee that MDA has given up trying and has terminated most of the optical signature analysis of flight data taken over the past 40 years. In the committee’s view, this is a serious mistake.

3.   It is clear that advances in technology for both long-wave infrared sensors and X-band radars that can coherently integrate and do Doppler imaging are impressive and offer new opportunities. The fundamental concept for maximizing the effectiveness is presented below (see classified Appendix J for greater detail).

4.   In addition to its long-term cost and performance advantages, the recommended GMD evolution as provided in the following sections of this chapter, if adopted, would decouple the defense of North America from decisions and issues related to the configuration of NATO missile defense, even avoiding altogether the need for PAA.


In short, the recommended GMD-E involves a smaller, shorter burn interceptor configuration that builds on development work already done by MDA under the Kinetic Energy Intercept (KEI) program, but with a different front end. The heavier, more capable kill vehicle (KV) with a larger onboard sensor provides

The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement