It is now some ten years since the last serious debate in the United States over nuclear strategy. That debate revolved around the issue of whether, to what extent, and in what role to deploy an anti-ballistic-missile (ABM) system designed to protect our cities and/or our own missiles from a nuclear attack. In one sense, the debate was settled by the ABM Treaty of 1972, which limited ABM systems in such a way as to encourage the eventual termination of an existing American ABM program and to discredit in the eyes of the American public the entire notion of ballistic-missile defense. In another sense, however, the debate was not settled, but merely ended. It was not settled on its technical or strategic merits so much as ended on the one hand by the requirements of the SALT process (of which it was a part), and on the other by the anti-military sentiments generated in the Congress and the country at large by the Vietnam war.
Now, eight years later, the ABM Treaty has become so much a fixture of American policy that its continuing utility seems to be simply assumed by all parties. Indeed, the ABM Treaty is still very widely regarded as the greatest success of U.S. arms-control policy in the postwar period.
Yet is it so clear that Americans should continue to congratulate themselves on the utter vulnerability of the North American continent to Soviet attack? The reassessment of U.S. military needs that has been stimulated by the Afghan crisis ought to address itself to this question, and the best way to begin is by recalling briefly the terms of the ABM debate as well as the early developments which preceded and stimulated it.
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By 1964 or 1965, it began to be apparent that the Soviet Union had decided to undertake a massive and comprehensive improvement in its military posture. The Soviets had let it be known that they would never again allow themselves to be faced down by superior American power, as had occurred in the Cuban missile crisis of 1962; and it is likely that they were already turning their attention to the prospect of a hostile China on their borders. Central to the Soviet effort were new strategic programs involving defensive as well as offensive systems. As early as 1964, the Soviets unveiled the Galosh ABM system, which was intended to defend the Moscow area, and they began construction of an extensive air-defense network with high-altitude interceptor missiles (the Tallinn system) that was believed by elements of the American intelligence community to have some ABM capability, or at least the potential for acquiring such a capability. At the same time, China was showing signs of strategic life. The first Chinese nuclear explosion occurred in the fall of 1964, and in 1965 the Chinese began constructing a ballistic-missile test facility.
These events gave a powerful impetus to ABM development in the United States. Because the intercontinental ballistic missiles (ICBM’s) possessed by the Soviets in the mid-1960’s were relatively few and inaccurate, American ABM efforts were originally directed toward providing protection for cities rather than weapons. Two types or levels of ABM defense were considered by U.S. military planners: a “thick” defense against all-out attack by the Soviets, and a “thin” defense against attack by the Chinese or against accidental missile launches. In spite of substantial disagreement within the U.S. government (and within the Pentagon in particular), President Johnson and Secretary of Defense Robert McNamara decided in 1967 to proceed with the development and eventual deployment of the “thin” or anti-Chinese alternative, which became known as the Sentinel system.
In the meantime, the idea of negotiating limitations on strategic arms with the Soviet Union was gaining headway in Washington. Early in 1967, options for strategic arms control, including limitations on ABM systems, began to be seriously considered, and contacts were initiated with the Russians. While generally receptive to these American soundings, the Soviets initially displayed considerable distaste for any ABM limitations. At a news conference in London in February, Premier Kosygin responded to a question concerning a possible moratorium on ABM development by asserting, among other things, that an anti-missile defense “is not a cause of the arms race but represents a factor preventing the death of people.” Nevertheless, the Russians went along with the American interest in comprehensive limitations, especially after the Johnson administration had announced its intention to proceed with the Sentinel system later that year.
Preparations for SALT were far advanced when the Soviet invasion of Czechoslovakia in August 1968 temporarily froze U.S.-Soviet relations. Apparently as a result of relatively strong sympathy on the part of the American military for ballistic-missile defense, the U.S. negotiating position would have called for high ABM limits and attempted to protect Sentinel, though it was far from inflexible on this point. In any event, with SALT in suspension and popular disaffection with the Vietnam war on the increase, it soon appeared that Sentinel was more in need of protection from the American public and Congress than from Soviet negotiators. Rising protests in the Senate induced the newly arrived Nixon administration to suspend Sentinel deployment in February 1969 and to review the entire ABM situation.
The result was a refurbished ABM program with a new name—Safeguard—and a new focus. While subscribing to the anti-Chinese and anti-accident rationale, President Nixon made clear that the primary task of an American ABM system would be to defend American ICBM’s. The reason for the shift was the rapid deployment of the very heavy SS-9 ICBM by the Soviets during this period, which for the first time posed a plausible threat to the American Minuteman ICBM force. The Safeguard system was to make use of most of the components developed for Sentinel, but it would protect Minuteman fields as well as major cities. Somewhat less costly than Sentinel, it was to be deployed eventually at a total of twelve sites, with the Minuteman fields having priority.
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In the six months that followed, the future of Safeguard became a subject of intense debate, and the focus for a wider public discussion of the fundamentals of American nuclear strategy. In August, the Senate finally authorized funding for the first two Safeguard sites. But a vocal opposition came within a single vote of killing the program; in the prevailing political atmosphere, the arguments against ABM in general and Safeguard in particular made their mark, and the future of the system had clearly become problematic. In July 1970, after SALT was fully under way, the Senate Armed Services Committee rejected an administration request to proceed with four additional Safeguard sites intended for area defense, thus effectively ending any prospect for ABM defense of American cities. Meanwhile, the Russians were making it clear that any progress on limiting offensive strategic weapons was dependent on American willingness to accept stringent limitations on Safeguard. The next two years of SALT were to be largely consumed in seeking a formula that would honorably inter the Safeguard system and the American commitment to strategic defense.
The arguments against a substantial American ABM system were of several kinds. In the first place, questions were raised about the effectiveness both of ABM defense generally and of the Safeguard system in particular. The shift from the defense of cities to the defense of our own missiles as the primary ABM mission may have made sense on strategic grounds, but it opened Safeguard to a variety of technical criticisms. Partly in response to objections that an anti-Chinese or anti-accident mission could not justify the cost of a substantial ABM system, the Nixon administration redefined Safeguard so as to give it a primary mission that could only be anti-Soviet; but the system’s components had not been designed primarily with a view to a “thick” Soviet attack. Accordingly, doubts could plausibly be raised regarding the ability of the Safeguard radars to track many targets simultaneously and to operate effectively in a nuclear environment. It was also widely argued that ABM radar technology would be unable to keep pace with the ability of the Soviets (or even the Chinese) to saturate the defense with “penetration aids” or decoys, and eventually with multiple independently targetable reentry vehicles (MIRV’s).
In the second place, and more importantly from the perspective of public and congressional opinion, ABM defense was held to be “destabilizing” or “provocative.” There were two variations on this theme. ABM was said to be destabilizing in the sense that it threatened to fuel the strategic arms race between the U.S. and the Soviet Union, and also in the sense that acquisition of an effective (or an apparently effective) ballistic-missile defense might give one side more of an incentive to launch a nuclear strike in a period of severe crisis.
Behind the latter argument was the strategic view that had achieved orthodox status during the 1960’s—the view that stable nuclear deterrence requires each side to possess an “assured” (that is, a “second-strike” or retaliatory) capability of inflicting unacceptable damage on the population and industrial resources of the other. Under the logic of “mutual assured destruction” (MAD, in its inevitable abbreviation), ABM and every other form of strategic defense are undesirable because, by demonstrating belief in the possibility of defense against nuclear attack by the other side, they suggest belief in the possibility of successful nuclear attack by one’s own side. Thus they threaten the other side with a preemptive first strike and create a situation of “crisis instability” in which both sides have strong incentives to initiate a nuclear exchange. By contrast, so the argument goes, a condition of complete mutual vulnerability is the most effective deterrent to nuclear war because it makes the very idea unthinkable.
The chief defect of this view as an argument against ABM defense is that it applies only to area or population defense, not to the defense of missile sites. Indeed, the defense of missile sites (or of other strategic-offense systems, such as heavy bombers) is wholly laudable under a MAD rationale since it helps guarantee an assured second-strike capability and hence the basis of stable deterrence. This was admitted at the time by many of the critics of Safeguard deployment. But it was argued that Safeguard was not well-suited to a site-defense mission, and that an extensive ABM network dedicated to site defense would be destabilizing in any event because it would serve as a base for rapid expansion to a system of area or territorial defense.
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II
When one looks back on the ABM debate and the treaty in which it issued, what is most striking is the massive and almost willful failure of anti-ABM forces to give serious attention to Soviet attitudes. The tendency was to treat the Soviets as recalcitrant and somewhat obtuse children who needed patient education in the realities of the nuclear era. American civilian strategists and arms-control enthusiasts with advanced degrees from universities like Harvard and MIT tended to look on the Soviet leadership fundamentally as a collection of untutored peasants bemused by the size of their ICBM’s and by mere quantities of such things as tanks and air-defense missiles. They regarded the Soviets as living in a strategic past, insensitive to the full implications for military strategy of the large nuclear arsenals accumulated by the two superpowers. That Soviet attitudes reflected a political and military culture very different from, but in its way not less sophisticated than, its American counterpart was a possibility not taken into account.
In retrospect, it is hardly clear that the Soviets have behaved more naively during the past ten years than an American leadership which remains bemused by technical sophistication at the expense of size and numbers, which has often shown itself insensitive to the political implications and uses of military force, and which has allowed its military planning to be shaped by an arms-control theology that is increasingly detached from international reality. On the crucial point—the Soviet understanding of the nature of nuclear war—the least that can be said is that the Soviets are so far from being unaware of the alternative represented by American strategic thought that they have considered and rejected this alternative. After some internal debate on the matter, the Soviets opted for the view that the existence of nuclear weapons does not alter the fundamental laws of military strategy, and that nuclear war is therefore not unthinkable in the sense that it is incompatible with any rational strategic or political objective. While recognizing the deterrent function of nuclear weapons, the Soviets have refused to follow the American example in according deterrence—as distinct from the requirements for actually fighting a nuclear war—the dominant role in nuclear planning. This does not mean that the Soviets are eager for nuclear war. It means that they believe it is necessary to be prepared to fight such a war in the event that deterrence fails.
The Soviets’ attitude toward strategic defense follows directly from their general outlook. For them, the fundamental requirement of defense of the homeland weighs more heavily than any abstract calculation based on assumptions about the intentions of potential enemies. While the Soviets almost certainly do not believe that a defense against American nuclear attack could be entirely effective, they do not see this as a reason for abandoning all efforts at defense. The Soviet leadership continues to invest enormous sums in air defense, and it has made serious and systematic efforts to provide protection for its population and for a wide range of military and industrial targets within the Soviet Union. All this is in contrast to the decrepitude of current air- and civil-defense programs in the United States—the result in very large part of the dominance of MAD thinking in American leadership circles during the 1960’s and 70’s.
Against this background, it is difficult to understand how American strategists and politicians were able to persuade themselves that the Soviets shared, or with some tutoring could come to share, the American view of the evils of ballistic-missile defense. Against this background, too, it goes almost without saying that the conclusion of the ABM Treaty did not end Soviet interest in ABM development.
Probably because of its manifest deficiencies, the Soviet Galosh ABM system was never expanded beyond the 64 launchers deployed in the Moscow area, but since 1972 the Soviets have done extensive work on possible successor systems. In addition, evidence has come to light that the Soviets may have conducted surreptitious testing of a high-altitude air-defense system (the SA-5) in an ABM mode during 1974 and 1975, contrary to Article VI of the ABM Treaty. Though overshadowed by other issues in the American debate over Soviet compliance with the SALT I agreements, the SA-5 matter was one of the most important of the alleged violations from a military point of view. During the 1960’s, much concern had been felt by elements of the American military over the potential of the Soviet Tallinn air-defense system (which was based on the SA-5 missile) to be “upgraded” to an ABM capability; it was this concern which inspired Article VI of the treaty. The acquisition of even a modest ABM capability by the SA-5—now deployed in large numbers throughout the Soviet Union—could have strategic significance. Truly worrisome, however, is the ABM potential of the much more sophisticated air-defense systems now under development by the Soviets. Unfortunately, the loss of our technical monitoring stations in Iran has made it difficult to keep track of Soviet activities at their ABM test facility at Sary Shagan, not far from the Iranian border. (This reduction in our ability to verify the ABM Treaty has gone unmentioned in recent discussions of SALT verification issues.) In addition, the Soviets are reported to be developing an anti-tactical ballistic-missile system (ATBM), presumably for use in the European theater; the ABM potential of this system is uncertain, but it could be considerable.
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But even if one assumes that the Soviets have not cheated on any treaty obligations and will not be tempted to do so in the future, it must be stressed that the ABM Treaty simply does not impose meaningful constraints on their ability to provide themselves with an effective ABM system. Nothing in the ABM Treaty prohibits the Soviets from engaging in research, development, testing, and production of the components of a new ABM system. These components could be stockpiled until such time as the Soviets saw fit to abrogate or terminate the treaty, and then rapidly deployed, either at the end of the six-month notice period or sooner. An action of this kind would certainly dismay many Americans; but respectable rationales for it could be imagined—the deployment of long-range nuclear missiles in NATO Europe, Chinese nuclear developments—that would disarm criticism elsewhere in the world and no doubt within certain segments of American opinion as well. The only technical constraint on such a move is the lead-time required for construction of the large phased-array radars which are necessary for initial tracking of incoming nuclear warheads. It is of more than passing interest that the other significant violations of the ABM Treaty with which the Soviets have been charged have concerned the construction of radars that could serve this purpose. But recent advances in radar technology will in any case greatly enhance the effectiveness of smaller and mobile or semi-mobile ABM radars which can be deployed rapidly and in large numbers.
It is surely a plausible hypothesis that the Soviets signed the ABM Treaty riot out of newfound conviction of the wisdom of MAD, but in order to arrest the planned deployment of the American Safeguard system and to dampen American interest in a strategic field in which this country held at the time a commanding technical lead, while simultaneously accelerating their own ABM efforts. If this is correct, however, the arguments employed against an American ABM system lose a great deal of their force. It is said that a treaty was necessary both to forestall competition in strategic defense and to remove an important incentive for competition in strategic offense (since the offense would have to remain capable of penetrating the defense). Yet it is hard to imagine what improvements the Soviets would have made in their offensive capabilities over the last ten years that they have not made under the terms of the treaty. As for competition in ABM development, an arms race has been averted only in the sense that the United States has dropped out of it. It is hard to imagine what the Soviets would have done in strategic defense, given their initial position of technical inferiority, that they have not done under the ABM Treaty.
Moreover, just when the U.S. was renouncing the right to provide effective defense of its ICBM’s and other “hard” installations, the Soviets were beginning to mount a serious offensive threat against precisely these targets. Continuing and unexpectedly rapid improvements in missile accuracy together with the unforeseen increase in missile throw-weight stemming from the deployment (contrary to the U.S. understanding of the terms of the SALT Interim Agreement) of the SS-19 ICBM have since brought this threat to crisis proportions. We are now, or will soon be, in a situation where a Soviet attack on the United States could destroy over 90 per cent of our Minuteman ICBM’s, do substantial damage (probably more than is officially admitted) to our B-52 bombers, and eliminate the quarter to a third of our ballistic-missile submarine force which happened to be in port, while holding very strong forces in reserve to deter a retaliatory attack against Soviet cities. This is a situation which would give the Soviets considerable incentive to preempt. The SALT process has failed entirely to fulfill the hopes of those who imagined it would create an era of unprecedented strategic stability. And far from alleviating the problem, the ABM Treaty has only aggravated it. For, by effectively prohibiting the defense of ICBM’s, it has caused us to deny ourselves what may well be the best remedy for our growing strategic vulnerability.
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Yet this is only to beg what many opponents of ABM will argue is the decisive question. Granting that an ABM defense of ICBM sites (and perhaps of other military targets such as bomber bases) could contribute importantly to strategic stability, is it not the case that ABM site defense is inextricably linked with ABM area or territorial defense, and that ABM area or territorial defense is so fundamentally threatening to strategic stability that it must be avoided at all costs?
In the first place, while there is no denying that conventional ABM systems utilized for site defense would also provide a basis for expansion to a territorial defense (particularly with the development of smaller and mobile radars), some attention is now being given to a variety of unconventional schemes for localized defense of ICBM fields which would not have this potential. The point should also be made that it is hardly clear that a limited site or area defense would provide a significantly greater basis for expansion to a territorial defense than what is obtainable under the ABM Treaty.
As for the allegedly destabilizing character of a territorial ABM defense, it must be pointed out that this issue cannot be meaningfully treated as an abstract problem in game theory, as regularly happens in American strategic literature. What American leaders are likely to do in an acute crisis will depend at least as much on the formative influence of the American political and military culture as on instant calculations concerning nuclear-exchange ratios and similar matters. It is nearly inconceivable that an American President would issue an order for a nuclear first strike against the Soviet Union on the strength of a string of hypotheses relating to the effectiveness of an ABM defense in warding off Soviet retaliation. No matter how reliable and effective an ABM system the United States felt it had developed, residual uncertainties regarding the performance of the system under conditions (which are only partly predictable with any confidence) of real nuclear war would always be a powerful constraint. In addition, the capacity of the Soviet Union to inflict damage on American military forces and on American allies around the world, together with the truly incalculable global consequences—political as well as military—of a nuclear exchange between the superpowers, would remain formidable barriers to any such decision.
These considerations also apply, it should be noted, to the Soviet Union. In the Soviet case, however, the military culture, with its emphasis on preemption of attack through massive strikes against the enemy’s military forces, tends in itself to promote crisis instability. But this is so far from being an argument against an American ABM system that it is one of the strongest reasons in favor of one.
With all this said, it can be added that the rationale initially offered for an American ABM system is as powerful today as it was in the late 1960’s. Although both the U.S. and the Soviet Union have made significant strides in the recent past in enhancing the reliability of systems designed to warn of nuclear attack, and of techniques and procedures for unilateral control of nuclear weapons as well as for cooperative handling of untoward nuclear events, the fact remains that an accident of potentially disastrous proportions cannot be ruled out altogether. It is unlikely that the accidental or unauthorized launch of one or a few missiles would lead to a full-scale nuclear war, but it could certainly cause immense damage.
As regards the anti-Chinese rationale, the fact that China has not yet developed a real intercontinental nuclear capability, and the fact that we are at present functionally allied with that country, should not blind us to Chinese ambitions and to the instabilities of Chinese politics. But the anti-Chinese rationale remains valid today not merely because of China, but also because of the threat of nuclear proliferation in the radical nations of the Islamic world. The interest that has been shown by the governments of Libya, Iraq, and Pakistan in acquiring nuclear weapons is well known, and it should not be necessary to emphasize the point that countries of this sort seem particularly inclined to produce reckless and fanatical leaders. It is true that in the near future this argues the need not so much for ABM as for improved air defense; yet the proliferation of ballistic-missile technology in less advanced states is a development which cannot simply be discounted. The spectacle of an embassy’s-worth of Americans held hostage by an Iranian mob would surely be as nothing compared with the nightmare of an entire city held hostage by the nuclear threats of a government claiming not to be deterred by the prospect of martyrdom.
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III
Still, how effective could an ABM system be under current circumstances? Is an ABM defense feasible or affordable given the prospect of continued improvement in strategic offensive capabilities? Would it not merely stimulate a new and costly arms race?
While the inevitable uncertainties of a developing technology make it impossible to answer the first question categorically, there appear to be considerable grounds for optimism. Again, it is necessary to distinguish carefully among varieties of possible ABM missions. Technical arguments that may have a measure of validity when brought against a thick territorial defense mission may not apply at all to thin territorial defense or to site defense. To defend effectively hardened targets such as ICBM silos, it is not necessary to destroy attacking warheads far from their destination, but merely to degrade their accuracy; and something less than total reliability is not a fatal defect. Hence inexpensive low-technology systems—for example, artillery shells that spray steel pellets in the path of incoming warheads—could be highly effective for site defense, especially when compared with the cost of offensive warheads. Even in the case of territorial defense, however, recent developments have gone very far toward refuting the technical objections that contributed to the defeat of Safeguard.
Conventional ABM technology, to begin with, has profited vastly over the last decade from the advances in data-processing and guidance systems that have revolutionized missile warfare at all levels. The development of precision-guided (“smart”) ABM interceptor missiles—missiles equipped with on-board scanners and computers for automatic homing on attacking warheads—is well under way at the present time. American military planners envision a “layered” ballistic-missile defense involving both an improved version of Safeguard for low-altitude (or “terminal”) defense and a system for the interception of incoming warheads prior to their reentry into the atmosphere. Under this concept, warning of a Soviet ICBM strike would trigger the launch of rockets carrying optical sensors that would be scattered in near space to assess the attack and direct the launch of other rockets that would dispense small non-nuclear homing vehicles; warheads not destroyed in this encounter would then be engaged again within the atmosphere.
Such a system would improve dramatically on Safeguard by increasing the time and opportunities for interception, by reducing reliance on a network of expensive and vulnerable ground radars, and by permitting the substitution of high-explosive for nuclear warheads (which are both expensive and subject to cumbersome procedures for authorizing their use). For purposes of site defense, such a system would appear quite able to hold its own in terms of cost with the offensive weaponry that would have to contend against it.
The layered concept also holds much promise for territorial defense. What may prove truly revolutionary in this connection, however, are unconventional ABM systems based on so-called directed-energy technology, particularly high-energy laser technology. The development of lasers as antimissile weapons is by now relatively far advanced, and they are likely to prove useful eventually in a variety of air-defense roles. But recent tests in this country have also shown that laser weapons could be considerably more lethal against Soviet ballistic missiles than had previously been thought. The most promising variety of laser ABM would be a system deployed in space (where beams can propagate over great distances—thousands of miles—with relatively little degradation) and designed to destroy hostile missiles shortly after launch, while they are in the vulnerable boost phase and prior to separation of their reentry vehicles (thus negating any advantage deriving from a proliferation of MIRVed warheads or penetration aids). Such a system, based on a network of perhaps two dozen satellites providing continuous global coverage, would be theoretically capable of countering not only ICBM’s but also submarine-launched ballistic missiles (SLBM’s), land-based intermediate-range ballistic missiles (IRBM’s) targeted against NATO Europe, and strategic bombers in high-altitude flight profiles.
Futuristic as all this sounds, the technology it would require is essentially proven, and proponents of the concept claim that, with proper levels of funding and political commitment, a first-generation laser ABM could be tested and deployed well before the end of the decade. While perhaps not fully effective against mass salvos of ICBM’s because of limitations on retargeting and rate of fire, a first-generation system could still respond very impressively to such an attack, and it could be exceedingly effective against SLBM’s (where launches must be staggered). Passive counter-measures to harden their missiles against laser effects could provide the Soviets a degree of protection, but only at a significant cost in missile payloads. In any event, subsequent generations of laser systems incorporating technical advances which can now be anticipated (primarily involving a shift from infrared to ultraviolet lasers) could render such efforts largely ineffective. Against active countermeasures—Soviet attack on the laser stations with anti-satellite weapons—the system would conveniently provide for much of its own defense.
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IV
But would an American move to ABM defense not merely perpetuate the “action-reaction cycle” that is supposed to fuel the Soviet-American arms race? Would it not also create a new competition in strategic defense, and in offensive countermeasures such as the maneuverable reentry vehicle (MaRV) now in an early stage of development?
It would be foolish to deny that a serious return to ABM defense would have large consequences for the future direction of strategic programs in both the United States and the Soviet Union. But it is necessary to ask, in the first place, whether the hope of ending the arms race by mutual arms limitations or by unilateral restraint is not essentially chimerical, and in the second place, whether an arms race in strategic defense is not in some ways more desirable than the available alternatives. That a serious move toward ABM defense by the United States would actually enhance strategic stability in crucial respects was suggested earlier. That the Soviets are likely to engage in intensified competition in this area were we to do so is probably true. Yet once faced with the prospect of competing in a technological game in which this country enjoys and will certainly continue to enjoy important advantages, it is conceivable that the Soviets would prove much more amenable to strategic restraint than they have when faced with American disinterest and inaction.
What are the alternatives to ABM defense from the point of view of maintaining or restoring a stable strategic balance? The primary source of strategic instability in the 1980’s is the growing vulnerability to a Soviet first strike of the American land-based missile force. There are only two ways of alleviating this problem, given the failure of arms-control solutions: ICBM’s either must be defended, or they must be made mobile. (A third alternative—launch on warning or under attack—would appear to be a poor substitute.)
Current American plans call for the development of a mobile ICBM, the so-called MX, which would be based in a deceptive manner in order to frustrate Soviet attempts to target it accurately. But apart from the fact that MX is expected to be enormously expensive (on the order of $40 or $50 billion), serious doubts can be entertained with regard to both its military effectiveness and its political palatability. Some administration spokesmen have made the argument that SALT II is in America’s interest because the limits it contains on “fractionation”—on the number of MIRV’s permitted on a missile—will guarantee the viability of the deployed MX system against a putative expansion of the Soviet offensive threat. This is less an argument in favor of SALT, however, than an argument against MX, since it would make the MX hostage to the tender mercies of Soviet negotiators in SALT III. Other questions have been raised concerning the reliability of the various deceptive-basing schemes which have been considered for MX, given projected improvements in remote-sensing technologies that could penetrate them. Moreover, it now appears that MX could not be fully deployed before 1989 at the earliest.
Apart from possible technical inadequacies, though, MX has been anathema to American arms controllers, who argue that its throw-weight and accuracy will enable the U.S. to pose a credible first-strike threat against Soviet ICBM silos, thereby undermining strategic stability. MX’s technical shortcomings may be more apparent than real; the arms-control argument is weak for an MX force of the limited size currently projected. What is more important, however, is the probable impact of these doubts and objections on American public opinion. With the Rube Goldberg flavor of its basing options and their potential for environmental disruption, MX could be expected to run into domestic difficulties no matter how sound the arguments in favor of it. When faced with vehement opposition from wide segments of liberal opinion—which will certainly surface as soon as the Afghan dust settles—MX will be in serious trouble. No amount of assurance by the current administration can make anyone feel comfortable about putting so many of our strategic eggs in the MX basket.
This is not to suggest that an ABM defense of Minuteman missiles presents a simple alternative to MX. (There are persuasive reasons unrelated to survivability for the development of a new ICBM: the larger MX would help rectify the throw-weight imbalance between American and Soviet strategic offensive forces, and provide needed flexibility in targeting an expanded number of hardened Soviet targets.) Rather, it is to suggest that the option of ABM defense would open up a new range of strategic possibilities and pro Vide a cushion in American strategic planning that is currently lacking. In the first place, an ABM site defense could be operational well before the deployment of MX in a land-mobile basing mode will be completed, and will thus be available at what is likely to be the time of maximum Soviet strategic advantage. Secondly, an ABM site defense could make possible the (temporary or permanent) deployment of some MX missiles in existing Minuteman silos, with potential savings in dollars as well as time. Finally, ABM could be utilized to protect or enhance the survivability of MX when it is eventually deployed as a mobile system.
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V
What, then, is to be done?
Plainly, the first order of business is a systematic and serious rethinking of the ABM question in all its aspects. This rethinking should take the form initially of a reconsideration of the fundamentals of American nuclear strategy from a perspective that is not determined by the theology and the history of strategic arms control. Then—but only then—it should proceed to reassess the achievements and the future promise of limitations on strategic offensive and defensive weaponry.
The question of strategic defense generally will be central in such a rethinking, and attention will have to be given to the long-neglected areas of civil and air defense. But the ABM question will be fundamental, both because it is inseparable from the largest questions of nuclear doctrine and because the ABM Treaty has evolved into a document of considerable symbolic importance for U.S.-Soviet relations and for the entire enterprise of strategic arms control. The approach of the next ABM review conference in 1982 is bound in any event to stimulate new interest in this matter in American defense and foreign-policy circles. But that conference could have disastrous consequences for American interests if it is not preceded and prepared by a comprehensive review of U.S. strategic requirements for the 1980’s. It should be added that if the United States does not move to reestablish the linkage between ABM and strategic offense, we are likely to find the Soviets doing it for us. In an ominous but not wholly implausible scenario, the Soviets could enter the 1982 conference with the position that, in view of Soviet advances in ballistic-missile defense, the United States must purchase continuation of the ABM Treaty with restrictions on its strategic-offensive programs—and particularly MX.
From a military point of view, the choices with respect to ABM roles and missions remain essentially what they were in 1969. The fundamental alternatives are site defense (in the first instance of ICBM silos, but also of strategic installations such as bomber and submarine bases and command centers), thin territorial defense (against third-party or accidental attack), and thick territorial defense (against full-scale Soviet attack). Strongest and least controversial in a doctrinal sense is the case for site defense, and this will and should have priority in future discussions of the question. Also strong, in spite of having been lost from sight following the demise of Safeguard, is the case for a thin territorial defense.
As for the third alternative—defense against full-scale Soviet attack—while it is bound to stir bitter controversy and may in the end prove politically impossible, it cannot be lightly dismissed. Of its many strategic advantages, not the least significant would be its effect in restoring credibility to the American commitment to the defense of Europe. A space-based laser ABM system may be the only real way to neutralize the new threat to NATO Europe represented by the Soviet SS-20 intermediate-range ballistic missile that is now being deployed in large numbers in the USSR; and it would surely make more plausible the U.S. threat to employ nuclear weapons in the European theater in response to a conventional invasion by Soviet and Warsaw Pact forces.
From an arms-control point of view, the only alternative that seems entirely unacceptable is maintaining the ABM Treaty regime in its present form. At the very least, the U.S. should seek clarification from the Soviets regarding the permissibility of site defense or of certain types of site defense within the terms of the present treaty; and it should insure that no avenues of ABM research and development (particularly relating to the possible use of space for ABM purposes) will be closed off through our unilateral interpretation of the requirements of the treaty or Soviet sensitivities to them. More radical alternatives would involve amending the treaty to allow an expanded site defense or thin territorial defense, while maintaining the current prohibition on expansion to a thick territorial defense.
Finally, of course, there is the alternative of abrogation. Even if the U.S. government will not have convinced itself by 1982 of the wisdom or feasibility of a thick territorial defense, this is a possibility that ought to be entertained seriously, especially if the Soviets show no inclination to moderate the growth of their strategic offensive forces over the coming decade. If the ABM Treaty is to be continued, it is the Soviets who ought to be made to pay for its continuation by taking meaningful steps to curb their progress toward a first-strike capability against the United States. Decisive Soviet military superiority is an inexorable development only in the minds of those who believe that Americans will not—or should not—have the stomach for a reassertion of American power in the world. As the domestic reaction to recent events in Southwest Asia has shown, such thinking is at best premature.
