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National Security Decision Directive 119, Strategic Defense Initiative

Published January 6, 1984

This National Security Decision Directive, dated January 6, 1984, established and outlined the United States' strategic defense initiative, first referred to by President Reagan in his "Star Wars" speech.



The current strategy of nuclear deterrence based upon the threat of retaliation has been successful to date; but it is subject to a number of destabilizing factors in the next generation. The U. S. has actively sought to strengthen the stability and credibility of deterrence and reduce the threat of nuclear war through modernization of its strategic forces and by making significant arms reduction proposals. The Soviet Union's unwillingness thus far to consider true arms reductions, and its massive increases in strategic offensive forces have necessitated continued U.S. actions to preserve our deterrent capabilities. NSDDs 12, 13, and 91 establish Administration policy on strategic forces modernization and nuclear weapons employment and outline our continued adherence to the concept of nuclear deterrence as the means for protecting the security of the United States and our allies.

However, given the uncertain long-term future of offensive deterrence, I believe that an effort must also be made to identify alternative means of deterring nuclear war and protecting our national security interests. In particular, the U.S. should investigate the feasibility of eventually shifting toward reliance upon a defensive concept. Future deterrence should, if possible, be underwritten by a capability to defeat a hostile attack.

3. The Department of Defense shall manage the strategic defense program. The Secretary of Defense shall be responsible for the strategic defense program and is requested to create a specific management structure to implement the program. The program manager shall report directly to the Secretary of Defense regularly and shall be provided with authorities and responsibilities commensurate with the high priority of this initiative. The Secretary of Defense shall recommend the level of funding required each year to meet program objectives and be responsible for presenting the request to Congress. The Secretary of Defense shall periodically report progress in achieving program objectives to the President.

4. The strategic defense initiative will place principal emphasis on technologies involving nonnuclear kill concepts. Research on new strategic defense concepts utilizing nuclear devices should continue as a hedge against a Soviet ABM breakout.

The strategic defense initiative shall be presented in the FY85 defense budget proposal as a prudent implementation of the recommendations of the Defensive Technologies Study report. Statements describing the strategic defense initiative should be low key and closely coordinated to ensure that an accurate picture of the nature and scope of this R&D effort is presented to the public.

This NSDD supplants previous guidance regarding the strategic defense initiative.

Strategic Defense Initiative (SDI)

On March 23, 1983, the President expressed his vision that new and developing strategic defense technologies could offer the potential to enhance deterrence by eliminating the threat of ballistic missile attack against the U.S. and its allies.

The President directed that a set of studies be undertaken by the defense community to evaluate this potential. Those studies confirm that new and emerging technologies offer the potential for developing an effective defense against ballistic missile attack and that this could enhance deterrence. The fact that the Soviet Union is known to be actively engaged in ballistic missile defense programs also makes it important that the U.S. pursue a strategic defense option as one possible response to future Soviet actions in this area. The technology studies identified several options for pursuing this capability.

Based upon these study results and the recommendations of the national Security Council, the President considered a range of possible initial SDI implementation measures. On January 6, 1984, he signed a National Security Decision Directive initiating the first phase of a comprehensive and committed strategic defense research effort to establish the technological foundation on which future decisions could be based. The President is committed to the SDI and intent upon seeing it develop in a responsible and prudent manner so as to ensure the continuity and sustained effort required to develop options for a future President.

The President decided that, in 1984, the SDI should focus upon developing an effective program management structure and on defining the scope and direction of a long term research and technology demonstration program building on research already underway. The President has charged the Secretary of Defense to establish an effective management structure for the SDI within DOD and to appoint a dedicated program manager of considerable stature in keeping with the high priority of SDI. The program manager will have central control of budget planning and execution, including the ability to reprogram resources from less promising to more promising technologies. This centralized control, with decentralized execution through government research organizations, will provide a visible and accessible focal point.

A long term, but intensive, research and technology procram has been identified to support the SDI. The SDI is not a development and deployment program, hut rather a broad-based, centrally-managed research effort to identify and develop the key technologies necessary for an effective strategic defense. The research will be initially focused on technologies for:

  • sensing and tracking attacking missiles;
  • destroying attacking missiles and warheads;
  • command and control; and
  • survivability and sustainability.

The SDI will explore technologies which might offer the potential to engage attacking missiles in any of their four phases of flight (boost, post-boost, mid-course, and terminal). Certain capabilities are important in this respect:

  • global, full-time surveillance, and attack warning;
  • boost engagement;
  • mid-course discrimination;
  • high endo-atmospheric engagement; and
  • interconnected and survivable systems management and data processing.

For 1985, the practical fiscal limitations on the defense budget, coupled with the need to firmly establish a sound management structure and more precisely define the programmatic directions of the SDI, led the President to decide to approve a $250 million increment to previously budgeted DOD strategic defense activities. While this level of increase is necessarily less than some options presented to the President, it is an increase over the originally budgeted level.

The SDI will be pursued in a manner consistent with all existing arms control agreements, including the ABM Treaty. It is part of the President's vision that, eventually, effective strategic defenses could help promote additional agreements to reduce offensive systems.

The President expects to see the SDI evolve and mature over the next few years and envisions a continuing U.S. emphasis on it.

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