In March 1983, President Reagan challenged the US scientific community to find a way to render nuclear weapons `impotent and obsolete.' Since then, research on the Strategic Defense Initiative has accelerated, fueling the debate over whether a space-based defense is the best way to free the US and the Soviet Union from their 40-year nuclear rivalry. The following articles are excerpted from the March-April 1985 issue of Survival, published by the International Institute for Strategic Studies in London.
The Strategic Defense Initiative (SDI), announced by President Reagan in March 1983, is a range of possibilities, near- and long-term.
What is the SDI? It should be (a) an exploration of ways in which the stability of the existing system of offensive, retaliatory deterrence might be enhanced; (b) an exploration of ways in which the terms of deterrence might be transformed in favor of much greater safety for civilians everywhere; and it should be recognized as (c) the only remotely feasible path by which nuclear disarmament on a truly massive scale might be secured.
The SDI is not (a) yet a weapons program; (b) a promise that society as a whole can for certain be defended directly; (c) a quest after some ever-elusive, illusory ``ultimate weapon'' (such cannot exist); nor is it (d) a promise of political peace.
A very major portion of the case for proceeding with the SDI is the virtually self-evident fact that there are no attractive alternative paths to greater security.
The nuclear deterrence system familiar today, with very dominant offensive capabilities, is adequate all the time that it either functions as we intend or, as generally is the case, all the time that it is not severely tested. The enduring problem is that the future rests upon a nuclear deterrence system concerning which even a single serious malfunction cannot be tolerated.
The alternative to the SDI is not a happy world of super-stable, jointly well-managed offensive arsenals; instead it is a world of acute competition and anxiety over net war-fighting prowess that cannot withstand a single breakdown in the extant deterrence system. Not only is strategic defense not an alternative to disarmament, strategic defense is the only way by which nuclear disarmament worthy of the name might be achieved. In the absence of defense, no one knows how to achieve nuclear disarmament on
a scale such that civilization, and even the ecosphere itself, would not be at prompt or delayed fatal risk in the event of a failure of deterrence.
There is no prudent choice available other than to press on carefully to explore the possibilities of strategic defense. Only in the presence of multilayered strategic defenses would the superpowers be able to endorse a very radical scale of nuclear disarmament. With such defenses, East and West could live with a disarmament treaty that would not be verifiable with absolute confidence. In the absence of homeland defenses, the incentive to cheat on a disarmament regime would be matched only by the ease w ith which the Soviet Union could cheat.
Whatever may or may not be possible eventually by way of the active defense of cities, the first necessary steps must be intermediate capabilities. Whether or not it proves feasible to destroy ballistic missiles in their boost phase or post-boost phase, terminal, nonnuclear defenses could provide a very attractive and effective way of strengthening strategic stability.
Such defenses would have to promote massive new uncertainties in Soviet attack calculations -- calculations that already are beset with major technical, tactical, strategic, and political uncertainties.
Probably the single most frequent objection that is raised to the nearer-term aspects of the SDI and a defensive transition is that it will stimulate the arms race. This objection is really no more than a truism. Any US strategic-force development that threatens to thwart some aspects of Soviet strategy, to deny some measure of military advantage, may serve as fuel for Soviet competitive behavior. There are some interesting cooperative possibilities for a defensive transition, but those possibilities ca n rest only upon effective US competitive performance. SDI and arms control
Should the US decide to move with the SDI from technology exploration into weapons development, formal arms-control negotiations could assume great importance.
First, late in the 1980s, the US may wish to renegotiate the terms of the Anti-ballistic Missile Treaty of 1972 so as to permit development and limited deployment of defenses for strategic forces and strategic command, control, communications, and intelligence (C3I) facilities. American policymakers would confront a choice that relates to the heart of deterrence reasoning. Should they seek an arms control regime that would assist the prelaunch survivability of nuclear forces, though at the price of impe ded access -- courtesy of Soviet deployments of ballistic missile defenses -- to Soviet territory? Or, should the ABM Treaty be retained in its pristine form, at the price of denying US forces and C3I a potentially valuable measure of prelaunch survivability? In the opinion of this author it would be wise to choose pre-launch survivability rather than unimpeded access.
Second, later in the 1990s, or perhaps early in the next century, the opportunity could arise for a truly radical, benign restructuring of strategic forces through the arms control process.
There is no doubt that a large-scale reduction in the quantity of Soviet offensive forces, not to mention some qualitative restraints upon the forces that remained, would greatly enhance the prospective performance of strategic defenses. So, the problem then, as today, is one of negotiating leverage. President Reagan's vision of a much-reduced scale of nuclear threat is more likely to be achievable if the Soviet Union can be brought to believe that nuclear disarmament on a massive scale is in her net se curity interest.
Stated directly, Soviet leaders and strategic planners will need to look at actual and potential US competitive performance in defensive and offensive weaponry, and decide that they face an important military disadvantage if they choose to let the competition run its course in a legally unregulated fashion.
By way of a contingent prediction, if Soviet leaders believe that US offensive forces will fare considerably better against Soviet defenses than will Soviet offensive forces against US defenses, then they should be motivated to agree to negotiated reductions in offensive forces. In American perspective, given that the US is far more interested in protecting Americans than she is in threatening Soviet citizens, the US should be prepared to forgo some measure of military advantage conferred by the superio r penetrative prowess of her offensive forces, as a price well worth paying for the reduction in the scale and quality of the Soviet offensive threat. Nuclear ambush during a defensive transition?
Some critics of the SDI have expressed concern that, should the Soviet Union anticipate the US achieving a significant military advantage through defensive deployments, she may elect to take very forceful measures to prevent a US defensive transition, or addition, from maturing. Several responses to this valid concern are appropriate, but the leading one is to the effect that it must be a mission of the strategic offensive forces to guard the defensive transition. It so happens, as noted already, that v ery potent offensive forces should serve both to discourage Soviet adventurism in the near term, and in the longer term could serve to provide the Soviet Union with the incentive necessary to negotiate the major reductions in offensive forces that must enhance the effectiveness of US defenses.
The nightmare scenario of a desperate Soviet Union choosing to fight today rather than live with the consequences of a measure of military inferiority tomorrow, is thoroughly implausible.
Should Soviet leaders anticipate military disadvantage as the defensive transitions (on both sides) mature, the extant US offensive force posture, if properly modernized, would provide them with the most persuasive of reasons for eschewing prompt military adventure. SDI and the Western alliance
Critics of the SDI are able to point, accurately enough, to some disquiet in NATO-Europe over what US strategic defense deployments may imply for East-West relations and for US motives and prospective performance as a security guarantor. Space precludes detailed treatment of this issue here, but the following points are relevant:
Near-term strategic defense developments, for the enhancement of the pre-launch survivability of US strategic forces, would simply strengthen the familiar terms of nuclear deterrence.
Near-term, point-defense technology, if deployed in Europe, would greatly strengthen the stability of deterrence. Antitactical ballistic missile (ATBM) defense against shorter-range Soviet missiles would deny the Soviet Union an important measure of confidence concerning the prospects for conventional success. ATBM defense of NATO airfields, supply dumps, C3 facilities, transportation nodes, and the like would play a vital role in facilitating the defense of NATO-Europe and, ergo, M DBR in discouraging aggression.
Far-term defensive technology (probably space-based, or space-deployable) could protect US allies as well as the US herself. Moreover, if we can move into an era wherein the American homeland enjoys a growing measure of direct, physical protection, the willingness of US presidents to run risks on behalf of distant allies logically should be strengthened.
Soviet strategic missile defenses must work to challenge the credibility of the small national deterrents of France and Britain. For the longer term, should both superpowers deploy heavy, multitiered nationwide defenses, then small nuclear forces, no matter how sophisticated their penetration aids, would indeed lack credibility. Given the benefits of a defensive transition in strategic forces, and the likely very-high scale of effectiveness of theater and tactical missile defenses, NATO-Eu ropean countries should welcome the opportunity to be able to devote their attention wholeheartedly to the problems of local conventional deterrence. Conclusions
No one can say what the balance of technological and tactical advantage between offense and defense will be in 20 or 30 years. But we do know that the history of military technology records swings of the pendulum of advantage from one to the other; and that strategic offensive technologies today are relatively mature, while strategic defensive technologies are very immature -- meaning that for the next several decades at least the advantage in growth in performance potential ought plainly to lie with th e defense.
Lest there be any misunderstanding, this author is not predicting particular weapons, for particular missions, by particular dates, with particular costs. There is no way of knowing whether multitiered strategic defenses capable of rendering intercontinental and submarine-launched ballistic missiles as obsolete as the horse cavalry will be technologically feasible.
But there is a major, indeed an overwhelming, arms control case for investment in the SDI to explore the possibility that the defense could reassume a position of strategic preeminence.
Arms control as understood for the past quarter century embraces three principal objectives: to reduce the risk of war; to reduce the damage that might otherwise be suffered should war occur; and to reduce the burden of peacetime defense preparation. The SDI and the defensive transition to which it may lead: (1) can, even in the near term, assist critically in enhancing attack-planner uncertainties, and hence must help stabilize deterrence and thereby reduce the risk of war; (2) may, in the long term, b e the only way in which damage limitation can be enforced in the event of a breakdown in deterrence; and (3) given the sharp downward trend in offensive nuclear capabilities that a defensive transition eventually should encourage, it is at least possible that the economic burden of peacetime defense preparation will be no greater than would be the case were the US and NATO-Europe to continue to rely solely on an offensive nuclear deterrent.
It must be acknowledged that the West faces a sharply growing threat from Soviet air-breathing vehicles, such as manned bombers and cruise missiles. Hence, a defensive transition, to have strategic integrity, must include air as well as missile defenses.
Also, it would be foolish to ignore the unfortunate fact that the strategic nuclear deterrent does have a range of specific missions of the highest importance for foreign policy. If the political structure of Soviet-American relations remains much as today, then there will be a need to find strategic substitutes for the nuclear threat to the Soviet homeland. Even in the context of a mature defensive transition, the Soviet Union will still need to be deterred from pursuing military solutions to her most pressing political problems.