The Technologies Study concentrated on the most difficult aspects of a multitiered, four-phase ballistic missile defense system capable of defending against a massive threat--the technologies that pose the greatest challenge. The study team was primarily concerned with technologies whose feasibility would determine whether an effective defense is indeed possible.

1. Critical Technologies

Several critical technologies will probably require research and development programs of ten to twenty years to be ready for deployment as part of such a ballistic missile defense.

O Boost and

post-boost-phase intercept. As mentioned

о

O

O

counter

earlier, the ability to respond effectively to a very
large missile attack is strongly dependent on
ing it during the boost or post-boost phases.

Discrimination.

Dense concentrations of reentry vehicles, decoys, and debris must be identified and sorted out during the midcourse and high reentry phase.

Survivability. A combination of tactics and mechanisms to ensure the survival of the system's space-based components must be developed.

Interceptors. By using inexpensive interceptors in the the midcourse and early reentry phase, intercept can be sufficently economical to permit attacks on objects that may not be warheads.

O Battle Management. Tools are needed for developing battle-management software.

There is much still to be done. For example, the management of large computer systems will pose important challenges. Developing hardware will not be as difficult as developing appropriate software. Large packages of software (on the order of 10 million lines of code) for reliable, safe, and predictable operation would have to be deployed. Fault-tolerant, highperformance computing would be necessary. Not only must it be maintenance-free for many years, but it must also be radiationhardened, able to withstand substantial shock, and designed to avoid a sudden failure of the entire computer system. The management of interlocking networks of space-, air-, and groundbased resources would require the development an accurate means of transferring da ta between computer systems rapidly and accurately, through system-generated protocols. There must also be a means to reconstitute all or part of the system if portions of it are damaged or made inoperable. In addition, specific ballistic missile defense algorithms will have to developed for target assignment and a simulation environment for evaluating potential system architectures.

be

for

The problem of survivability is particularly serious space-based components. The most likely threats to the components of a defense system are direct-ascent anti-satellite we apons, ground- or air-based lasers, orbital anti-satellites, both conventional and directed energy weapons, space mines, and fragment clouds. On the ground, traditional methods to enhance survivability can be effective, such as hardening, evasion, proliferation, deception, and active defense. But to protect space-based systems, these methods must be employed in combination. Ideally, the defense system should be designed to withstand an attack meant to saturate the system. At the very least, the system's most critical points must be protected.

It is to

The history of warfare in general and the interactions of weapons technologies in particular indicate that for many potentially successful defenses counters have been developed. essential, therefore, to consider possible countermeasures the development of a ballistic missile defense. But countermeasures are likely to compete with other military programs for available resources and thus may result in diminished offen

sive capability.

For example, hardening of booster rockets of missiles (to withstand a boost-phase missile defense) results in either a reduced payload or a shorter range of the offensive missiles.

2. Logistical Support

The study also described research programs on space 10logistics that would take five to ten years to complete. In order of priority, the requirements are: (1) development of a heavy lift launch vehicle for space-based platforms of up to 100 metric tons (220,000 pounds one-time payload); (2) ability to service the space components; (3) ability to make available, or to orbit, sufficient materials for space-component shielding against attack; (4) ability to transfer items from one orbit to another; and (5) multimegawatt power sources for space applications.

Based on the Defensive Technologies Study, the Department of Defense, along with the Department of Energy, has established a new program for the President's Strategic Defense Initiative (SDI). Existing programs relating to the SDI have been focused in five technology areas, and additional funding will be sought to pursue them aggressively. In recognition of its importance, the Strategic Defense Initiative will be centrally managed and will report directly to the Secretary of

Defense.

The Strategic Defense Initiative represents one of the most important technological programs the Nation has ever embarked upon--a great hope for the future--but it does not represent a deployment attempt, nor is it a substitute for current strategic and conventional force modernization or for arms control. Rather, it will for sound deployment decisions.

create the technological base SDI will use America's greatest assets, our creativity and our ingenuity, to lessen the awesome threat of nuclear weapons.

Acknowledgments

This report is a summary of work performed by a Study Team whose members were: Mr. Fred S. Hoffman, Director; Mr. Leon Sloss, Deputy Director; Mr. Fritz Ermarth; Mr. Craig Hartsell; Mr. Frank Hoeber; Dr. Marvin King; Mr. Paul Kozemchak; Lt. Gen. C. J. LeVan, USA (Ret.); Dr. James J. Martin; Mr. Marc Millot; Mr. Lawrence O'Neill; and Dr. Harry Sauerwein. The work of the Study Team has been reviewed by a Senior Policy Review Group consisting of Professor John Deutch; Dr. Charles Herzfeld; Mr. Andrew W. Marshall; Dr. Michael May; Professor Henry S. Rowen; General John Vogt, USAF (Ret.); Ambassador Seymour Weiss; Mr. Albert Wohlstetter; and Mr. James Woolsey. Supporting papers have been contributed by Mr. Craig Hartsell, Dr. James J. Martin, Mr. John Baker, Lt. Gen. C. J. LeVan, Mr. Douglas Hart, Mr. Marc Millot, Dr. David S. Yost, Mr. Leon Sloss, and Mr. Frank Hoeber.

The Study also benefitted from comments and suggestions by Dr. Thomas Brown, Dr. Ashton Carter, and Dr. Thomas Rona.

The Panel also has had the invaluable cooperation of Lt. Col. Irving Schuetze, USA. Responsibility for the views expressed herein rests with the Study Team.

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