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Nuclear Arms Control: Background and Issues (1985)

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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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Suggested Citation:"1 Overview." National Academy of Sciences. 1985. Nuclear Arms Control: Background and Issues. Washington, DC: The National Academies Press. doi: 10.17226/11.
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~ Overview There is worldwide agreement that a general nuclear war would be a totally unprecedented human catastrophe. Civilization as we know it would be destroyed. The leaders of the United States and the Soviet Union have consistently proclaimed that a central objective of their national policies is to prevent such a disaster. Despite this common goal, the means of achieving it have been the subject of bitter controversy between the two superpowers. Within the United States, the lack of consensus is reflected in the heated debate on all aspects of the U.S.- Soviet relationship. To many, the nuclear arms race has become a symbol of the danger of nuclear war. Failure to contain the arms race has resulted in wide- spread concern and even despair about the prospects of avoiding nu- clear war. While not in itself the only, or even the central, cause of tensions between the superpowers, the nuclear arms race certainly in- creases the risk of nuclear war and the extent of the disaster that would result. The dangers of the arms race can be limited by mutual agreements or independent actions by each nation. Arms control agreements are cove- nants between potential adversaries defining the boundaries between what is forbidden and what is allowed in military activities. Such a covenant is by its nature a complex and controversial undertaking. The contributions that this approach has made or can make to reduce the risk of nuclear war can only be judged by examining actual arms control agreements or proposals. Only in the specifics of these covenants do the problems and the opportunities of arms control come to life. 1

2 NUCLEAR ARMS CONTROL The national debate on nuclear arms control, which has grown stead- ily in intensity over the the past few years, has focused primarily on a half-dozen international agreements and proposals. These are the un- ratified SALT II Treaty and the START proposals, which are directed at strategic offensive systems; the SALT ~ Anti-Ballistic Missile (ABM) Treaty, which has been placed in jeopardy by renewed U.S. emphasis on strategic defense systems; a comprehensive freeze on nuclear weapons and delivery systems; the Intermediate-Range Nuclear Force (INF) ne- gotiations which are directed at intermediate-range nuclear forces in Europe; a comprehensive ban on nuclear testing; and limitations on anti-satellite systems. To this list should be added a number of specific agreements and proposals directed at another aspect of the nuclear arms race, the proliferation of nuclear weapons to additional countries. The chapters following this overview present the background and status of these specific agreements and proposals and examine the un- derlying issues as seen by supporters and critics. This overview chapter examines a number of underlying issues, on which opinions differ widely, that recur in the debate on each approach. These are: · the desirability of arms control as a process; · the basic objectives of arms control; · the approaches to arms control agreements; · the status of the U.S.-Soviet strategic relationship; · the interaction of other nuclear states with the U.S.-Soviet strate- gic relationship; · the requirements for verification; · the record of compliance with existing agreements; · "linkage" of arms control to other DolitiCR1 or milit.~rv nhi~ntiv~ · the approach to the negotiating process; and · domestic acceptance of arms control agreements. ARMS CONTROL AS A PROCESS _ __ A _ my ~ ~ Most observers would agree that the dangerous confrontation be- tween the United States and the Soviet Union arises from the deep political differences that divide the two countries and generate mutual distrust. How best to moderate or eliminate these political differences has been the subject of recurring domestic debate. Some favor efforts to reduce tensions by developing areas of mutual interest that would en- courage Tong-term improvement in political relations despite continu- ing differences on major issues. Others favor increasing the pressure on the Soviet Union in an attempt to force a Tong-term change in Soviet

3 OVER VIEW political attitudes by confronting it on fundamental issues and by seek- ing to isolate it politically and economically. In the absence of real progress in resolving their political differences, the United States and the Soviet Union have to date sought to prevent nuclear war principally by developing more and improved nuclear weapon systems. These systems have been designed to deter the other side from using its own arsenal of nuclear weapons or from starting a conventional war on a scale or in circumstances that could escalate into general nuclear war. Thus, nuclear deterrence, where each side simul- taneously threatens to destroy the other, has ironically become the principal shield against the outbreak of nuclear war. A strong case can be made that nuclear deterrence has prevented the outbreak of war directly involving the superpowers since World War IT. Nevertheless, many people have long seen the very process of building up larger and more sophisticated strategic forces as substantially increasing both the likelihood and the consequences of nuclear war. After World War Il. nuclear disarmament leading to the elimination of nuclear weapons was widely advocated as the only way to prevent nuclear war. This approach, which was extended to include essentially all armaments as part of a program of "general and complete disarma- ment," was not only the slogan of pacifists but also of U.S. and Soviet leaders, who proclaimed it as an attainable goal at a time when both sides were rapidly building up their nuclear forces. By the mid 1960s complete nuclear disarmament, though still advocated by some as a realizable near-term goal, had lost much of its credibility. There were many reasons for this disillusionment, including the military doctrines of the nuclear powers, the high level of nuclear arsenals, the deep politi- cal divisions that existed not only between the United States and the Soviet Union but among other countries in many regions of the world, and the military significance of even small numbers of secretly retained nuclear weapons in an otherwise disarmed world. For the past 20 years, arms control, as distinct from disarmament, has provided an alternative to sole reliance on unilateral military prepared- ness as a barrier to nuclear war. Arms control defines the effort to "manage" the nuclear confrontation by mutual agreement in ways designed to lessen the likelihood of nuclear war. The arms control pro- cess seeks to constrain the size and nature of nuclear arms and their delivery systems to stabilize the strategic relationship. Despite wide differences as to the objectives and approaches of arms control, the basic concept is now generally accepted and considered an integral part of U.S. security policy. Domestic support for the concept, however, is not universal. Some critics assert that any agreement will

4 NUCLEAR ARMS CONTROL inevitably constrain the United States in the exploitation of its techno- logical advantages to improve its nuclear capabilities, which are the real deterrent to war. Other critics oppose the entire concept of arms control, contending that the net effect of any agreement, however favor- able the terms, would be to lull the United States into complacency, with necessary and permitted military efforts being neglected while the So- viet Union continues its military buildup. In various forms, this under- lying opposition to arms control reemerges in arguments against specific proposals. At the other extreme, arms control has been criti- cized as undercutting the real objective of nuclear disarmament. By accepting and institutionalizing nuclear arms and by adopting a gradu- ated approach to nuclear reductions, according to this perspective, arms control impedes efforts to reduce drastically or eliminate nuclear arms. Between these extremes exists a broad spectrum of opinion on the desir- ability and urgency of various forms of control on nuclear weapons. THE OBJECTIVES OF ARMS CONTROL The underlying objective of arms control is to increase the stability of the military relationship of the nuclear powers, thus reducing the risk of nuclear war. The objective of stability can be divided into two sepa- rate, and sometimes conflicting, concepts, "arms race stability" and "crisis stability." Arms race stability is achieved by stopping or moder- ating the competition in nuclear arms. This competition increases the risk of war by introducing more threatening weapons and by making more nuclear weapons available for expanded roles and missions. Crisis stability, on the other hand, is achieved by eliminating the incentive for either side to launch a preemptive counterforce attack in an effort to obtain military advantage by significantly blunting the other side's capacity to retaliate. The danger of such a counterforce attack would clearly be greatest at the time of a major political crisis or military confrontation, when escalation to nuclear war might be judged a real possibility. Agreements that establish mutual constraints on the size and quality of nuclear arsenals or ban certain activities completely contribute to arms race stability. By limiting existing forces and establishing a clear framework within which future forces are constrained, such agree- ments make the future U.S.-Soviet military relationship more predicta- ble. This reduces the pressure on both sides to pursue developments and deployments based on worst case assessments of the other side's uncon- strained future capabilities. Advocates of the importance of arms race stability argue that the elimination of such worst case assessments substantially reduces international tensions and the risk of war.

OVER VIEW 5 In an international context, efforts to prevent the further prolifera- tion of nuclear weapons also contribute to arms race stability. If addi- tional states acquire nuclear weapons, it clearly puts pressure on their adversaries to obtain their own nuclear weapon capability. The result- ing nuclear arms competition in unstable areas of the world would dangerously increase the unpredictability of not only regional political- military relations but also of U.S.-Soviet relations as well. Crisis stability, or the reduction of the risk of nuclear war in a crisis, can be increased by measures that assure the survival and effectiveness of retaliatory strategic forces in the face of a preemptive counterforce attack. Both the deployment of more survivable retaliatory systems and the elimination of highly vulnerable strategic systems that are tempting targets contribute to crisis stability. This objective can also be supported by constraining strategic offensive forces that threaten the survivability of retaliatory forces and by constraining strategic defen- sive forces that threaten to prevent retaliatory forces from reaching targets. A high level of crisis stability does not eliminate the possibility of military engagements escalating into nuclear war, but it does reduce pressure to preempt if nuclear war appears imminent by reducing the perceived need to use vulnerable weapons before they are destroyed. U.S. military policy has long sought to improve crisis stability by unilaterally maintaining diversified, survivable strategic forces capa- ble of penetrating Soviet defenses. The triad of land-based missiles, sea- based missiles, and bombers has been designed to assure retaliation after a Soviet preemptive counterforce attack that might severely de- grade one or even two legs of the triad. Although much more dependent on potentially vulnerable land-based strategic missiles, the Soviet Un- ion has also moved in the past 20 years to develop more survivable strategic forces by improving the sea-based component of its forces and by hardening the launchers of its land-based missiles. Despite unilateral efforts to reduce the vulnerability of strategic forces, current technical developments could in principle increase the future vulnerability of both sides' strategic forces and decrease their ability to penetrate defenses to reach targets. These developments de- crease crisis stability. Agreements that increase the survivability of retaliatory strategic forces, either by encouraging deployment of less vulnerable systems or by constraining the threat to these forces, would contribute to crisis stability above and beyond the unilateral measures that the United States and the Soviet Union might adopt. Arms control should not be assessed exclusively on its immediate contributions to arms race and crisis stability. There are clearly second- ary political and social objectives that some would argue may prove equally important in the long run. The process of negotiating mutually

6 NUCLEAR ARMS CONTROL acceptable agreements dealing with matters that affect both sides' very survival, and then living within this self-imposed regime, can build understanding and confidence between the superpowers. The resulting atmosphere of constructive cooperation in reducing the risk of war can also significantly reduce international political tensions. By increasing the predictability in the military relationship, arms control not only reduces the pressure to plan on a worst case basis but reduces political concerns about future intentions. Thus, a successful arms control re- gime could be a major factor in gradually reducing the political tension and distrust that have intensified the arms race between the United States and the Soviet Union. Another benefit often associated with arms control is that it would reduce military spending, freeing resources for the civilian economy. However, since less than 20 percent ofthe military budget is allocated to strategic nuclear forces, even far-reaching nuclear arms control agree- ments would affect only a small part of the military budget. There would also be strong pressures to invest savings from nuclear arms control in the modernization of conventional arms. In the longer term, however, if a successful arms control regime significantly reduced polit- ical tensions, the United States, the Soviet Union, and the world at large could profit enormously from the transfer of even a small fraction of military expenditures, now approaching $1 trillion annually, to con- structive nonmilitary purposes. APPROACHES TO ARMS CONTROL Arms control agreements have sought to enhance arms race and crisis stability by one or more of the following general approaches: limits, freezes, restructuring, reductions, bans, and special stabilizing mea- sures. Each of these ways to constrain nuclear weapons and their deliv- ery systems is discussed below. Limits Limits on various types of weapons or other measures of nuclear mili- tary~power are one approach to arms control agreements. By establish- ing limits at current or reduced levels of some agreed measure of military power (such as number of launchers or deployed missiles or total throw-weight), a quantitative ceiling can be placed on the arms race. Crisis stability can also be improved if modernization permitted under the ceilings results in more survivable systems. Limits that favor survivable systems and constrain threatening first-strike counterforce systems also favor crisis stability. The SALT II Treaty sought to contribute to both arms race and crisis

OVER VIEW 7 stability by establishing equal aggregate limits for both sides on their total number of strategic missile launchers and heavy bombers. A se- ries of separate equal sublimits further constrained these systems. The sublimits together with certain qualitative limits constrained the num- ber of multiple independently targetable reentry vehicles (MIRVs) and air-launched cruise missiles. The treaty also allowed the introduction of only one new type of intercontinental ballistic missile (ICBM), which could be deployed in a survivable mode, such as the proposed mobile MX with multiple protective shelters. The U.S. proposal at the START negotiations seeks to contribute to arms race and crisis stability by establishing separate equal ceilings and subceilings on deployed strategic missiles, missile warheads, mis- sile throw-weight, and strategic bombers. The U.S. proposal would cap the quantitative strategic arms race at substantially lower levels. It also seeks to encourage more survivable deployments and to reduce the counterforce threat of the large accurate force of Soviet ICBMs. The Soviet position at the START negotiations would essentially deepen the SALT IT constraints. Both the SALT II and START approaches would allow continued testing, production, and deployment of new nuclear weapon systems within clearly defined limits. The SALT ~ ABM Treaty is designed to prevent the deployment of nationwide ballistic missile defense systems. It limits the United States and the Soviet Union to a single ABM site apiece with no more than 100 fixed launchers and 100 interceptors. It also establishes specific limits on the radars associated with the system. Some system modernization is permitted within these quantitative limits, but specific provisions constrain the nature of the modernization so that it cannot be used to defeat the basic purpose of the treaty. For example, the two sides are not permitted to develop, test, or deploy launchers capable of launching more than one interceptor at a time or capable of rapid reload. Similarly, the treaty prohibits the development, testing, or deployment of ABM systems or components that are sea-based, air-based, space-based, or mobile land-based. By preventing the deployment of nationwide ballis- tic missile defense systems, it is argued that the ABM Treaty contrib- utes substantially to both arms race stability and crisis stability because such a system, whatever its capabilities, would be perceived as an attempt to develop a shield to negate the deterrent effect of strategic retaliatory forces. Freezes A freeze would stop all new activity in the area covered. This is quite distinct from limits, such as those in SALT I] and START, that would

8 NUCLEAR ARMS CONTROL permit modernization within the agreed limitations unless specifically prohibited. A freeze would permit the continued use of existing invento- ries of the system in question. A comprehensive nuclear freeze would prohibit the further testing, production, and deployment of all nuclear weapons and delivery systems. A comprehensive nuclear freeze would clearly meet the objective of arms race stability. There would be no further growth of the threat on either side, and the action/reaction cycle of the arms race would be broken. At the same time, a comprehensive freeze would have a mixed impact on crisis stability, because it would freeze the status quo with its problems as well as its advantages. On the one hand, such a freeze would prevent either side from introducing new, more destabilizing systems. On the other hand, it would prevent both sides from restruc- turing their strategic forces with new (or old) systems that would be less vulnerable or threatening. A number of arms control proposals have used the freeze approach in a limited manner. For example, SALT IT froze Soviet heavy missiles (no further deployments of any type and no testing of new types) and Soviet mobile SS-16 missiles (no further testing, production, or deployment). The Comprehensive Test Ban, on which final agreement was never reached, sought to freeze the development, production, and deployment of new types of nuclear weapons by prohibiting all nuclear testing, since testing was judged necessary to develop advanced new weapons. Restructuring Restructuring U.S. and Soviet nuclear forces could substantially im- prove crisis stability. Restructuring could eliminate threatening sys- tems with a counterforce capability, such as highly MIRVed high-accuracy missiles, and vulnerable high-value systems, particu- larly fixed launchers for highly MIRVed missiles, which would be Togi- cal targets for a preemptive counterforce attack. In some cases, such as the Soviet SS-lBs and SS-19s and the U.S. MX, the same system can be destabilizing in both respects. Agreements can permit or even encourage desirable restructuring without actually requiring it. For instance, SALT II allows fixed, land- based missile launchers to be replaced within the agreed limits by sea- based missiles or bombers, but it does not permit the construction of additional new fixed land-based missile launchers. The U.S. START proposal goes further and essentially requires the Soviet Union to give up a significant fraction of its deployed land-based missiles. In seeking crisis stability, restructuring proposals can be inconsistent with arms

OVERVIEW 9 race stability if they encourage or require major new nuclear arms programs to replace existing nuclear systems, such as the replacement offered land-based ICBMs with larger numbers of small, mobile, single- warhead missiles. Reductions Limits and restructuring can be at current or reduced levels, and a freeze can also lead to reductions. Even if modernization is permitted or encouraged, substantial reductions in measures of overall military nu- clear power tend to enhance arms race stability. Selective reductions of threatening systems can obviously improve crisis stability, but strictly proportional reductions in all systems, threatening and retaliatory alike, would have little effect on this objective of arms control. Substantial reductions could also reduce the risk of war by limiting the nuclear options available to both sides. This would make it less likely that nuclear weapons would be introduced in an escalating mili- tary situation. Substantial reductions could also reduce the possibility of accidental nuclear war, to the extent that this possibility depends statistically on the number of nuclear weapons deployed. At the same time, very large reductions could reduce crisis stability by making a preemptive attack more credible. Such an attack might be seen as re- ducing the opposing retaliatory force to a point where defenses could limit damage from retaliation to acceptable levels. With extremely large reductions, there would also be the problem that relatively small numbers of delivery systems that might be unaccounted for by the verification system could be judged a significant factor in assessing crisis stability. Bans The complete prohibition of an entire class of nuclear weapon sys- tems, including the elimination of existing stockpiles, and the halt of future development, production, and deployment could contribute dra- matically to both arms race and crisis stability if the activities banned constitute a significant present or future threat. To date, complete bans have generally been proposed for systems that do not yet exist. This avoids the difficult verification problems of dealing with undeclared stockpiles and standby production facilities. Such bans may still be very important if they close off a dangerous path of development before ei- ther side has a vested interest in it. The Outer Space Treaty, for exam- ple, banned the deployment of "weapons of mass destruction" in outer

10 NUCLEAR ARMS CONTROL space at a time when there were no programs or plans to pursue such activities. As noted above, the SALT ~ ABM Treaty banned the develop- ment, testing, and deployment of ABM systems or components that are sea-based, air-based, space-based, or mobile land-based at a time when neither side had any known plans for such developments. The proposed ban on anti-satellite weapons illustrates the problem of dealing with complete bans once systems have been tested and de- ployed. The Soviet Union has had a limited anti-satellite system in operation for a number of years, which raises the question of how to eliminate possible clandestine stocks that could be redeployed on short notice. In this and other cases, the significance of such a marginal capability must be balanced against the value of an overall ban on a dangerously destabilizing activity. A comprehensive test ban on all nuclear explosions, as noted above, amounts to a freeze on future nu- clear weapon developments rather than a ban on nuclear weapons. It would stop the development and deployment of new types of nuclear weapons, but it would not affect existing stockpiles or the ability to produce and deploy additional weapons of existing designs. Special Stabilizing Measures A large range of measures that are not related to the size and nature of U.S. and Soviet nuclear forces could increase crisis stability and reduce the risk of nuclear war by accident or miscalculation. One class of actions would seek to reduce the risk of nuclear war, particularly by accident or miscalculation, by helping to assure that both sides are operating with a correct understanding of the threatening situation and the other side's intentions. Improved communication between gov- ernments might facilitate this objective, as might direct communica- tion through permanent groups established to exchange information and resolve problems on a continuing basis. Another class of stabilizing measures would seek a partial disengage- ment of nuclear forces so that unauthorized or precipitous use of nuclear weapons in a limited, conventional military engagement would be less likely. For example, the two sides might agree to keep their ballistic missile submarines at distances from the other side beyond the range of the submarines' missiles, a concept whose significance obviously de- pends on the range of the missiles. Another example would be the with- drawal of forward-based tactical nuclear weapons some distance behind the line dividing NATO and the Warsaw Pact, thus reducing the pres- sure to use them in the earliest phase of a conventional battle if it appeared that they would be overrun by an enemy advance. In both

OVERVIEW 11 instances the question of the effect of such procedures on the credibility of the deterrent has to be faced. Another class of stabilizing measures would seek to reduce the vul- nerability of retaliatory systems and to build more time into the deci- sion-making process. For example, limits on how close submarines can approach the coasts of the other side could prevent attacks with drasti- cally reduced warning time on critical command and control facilities or strategic air bases. Another example would be to establish agreed sanc- tuary zones for ballistic missile submarines where neither side would engage in threatening antisubmarine warfare activities such as trail- ing the adversaries' submarines. These and other special measures could stand alone or be incorporated in any of the general approaches outlined above. THE U.S.-SOVIET STRATEGIC RELATIONSHIP Any arms control proposal must be assessed in terms of its impact on the present and future U.S.-Soviet military relationship. Thus, the sta- tus of the present and projected military forces of the United States, the Soviet Union, NATO, and the Warsaw Pact has been a critical factor in the arms control debate over the past 25 years. One can question whether "superiority" has any real military significance when the United States and the Soviet Union each have some 10,000 strategic warheads. Nevertheless, when either side has had, or has been per- ceived to have, a militarily or politically exploitable level of superiority, progress in achieving nuclear arms control agreements has proven diffi- cult. The role of perceptions of military capabilities must not be under- estimated; perceptions can play a much greater political role than the real military significance of apparently unbalanced forces. If either side seeks an agreement that establishes or permits a position of generally perceived superiority, there is little chance that it will be successfully negotiated and brought into force. The problem of assessing the strategic balance between the United States and the Soviet Union is greatly complicated by the major asym- metries in the strategic nuclear forces and other military forces of the two countries. These asymmetries reflect many underlying differences between the two countries. These differences include such factors as attitudes acquired over centuries of radically different historical expe- rience, military doctrine, political ideology, the economic base, rela- tions with allies, and potential adversaries. In general, the asym- metries in strategic forces can be associated with a variety of geo-

12 NUCLEAR ARMS CONTROL graphic, military, technical, and bureaucratic differences between the two countries. Geographically, the United States and the Soviet Union have radi- cally different access to the sea and proximity to potential adversaries. Militarily, the United States has a much stronger tradition of naval and air power. The Soviet Union has a much stronger historical emphasis on massive land armies and defense of the motherland. In these circum- stances, it is not surprising that the United States moved early to a triad of air, sea, and land forces while the Soviet Union emphasized land- based missiles and air defenses. Technically, the United States, with its substantial advantages in technology, moved sooner to smaller, more sophisticated systems while the Soviet Union emphasized larger systems of less sophisticated hard- ware. For example, the United States at an early stage developed small solid-propelIant missiles. This reflected the early availability in the United States of light thermonuclear warheads, miniaturized electron- ics, improved reentry technology, and advanced solid-fuel technology. The Soviet Union initially emphasized large liquid-fuel missiles that did not depend on these developments but could deliver large payloads. Bureaucratic politics, reflecting the difference between an open and a closed society, have undoubtedly also played a major role in the develop- ment of the two countries' forces. Both countries experience strong in- stitutional pressures to extend and expand ongoing programs. But in the United States there has been a relatively open and intense debate about the structure and procurement of strategic forces and their budg- etary implications. The top Soviet military leadership has held these decisions very closely, and vested interests within the Soviet Union, such as major design bureaus and the military services, have been able to maintain the momentum of the Soviet buildup with less evident interference from other competitors for scarce resources. With all of these basic asymmetries, it is not surprising that the structure and capabilities of U.S. and Soviet nuclear forces differ, not- withstanding a general pattern of action and reaction between the two sides and persistent Soviet efforts to match U.S. technological accom- plishments. It is also not surprising that within the United States there has been a continuing controversy about the status of the strategic balance. The inherent complexity of the problem, particularly when coupled with the strong political emotions surrounding it in both coun- tries, has been a major factor in the difficulty in negotiating mutually acceptable arms control agreements. A brief historical review recalls the changing nature and perceptions of this strategic relationship and the reaction to it on both sides. In the

OVER VIEW 13 late 1940s the United States hac! an absolute monopoly of nuclear forces. Throughout the 1950s it had a sufficient advantage in the num- ber and quality of its strategic forces to be judged as having strategic superiority. At that time the United States declared a policy of massive retaliation to deter a perceived Soviet conventional military threat against an unprepared Western Europe. Yet even in this period of appar- ently overwhelming U.S. advantage, some sophisticated U.S. analysts believed as early as the mid-1950s that serious crisis instability was developing because of the perceived extreme vulnerability of U.S. stra- tegic forces to surprise attacks by Soviet forces. In the 1960s the United States developed a triad of air-, sea-, and land- based strategic forces. The objective was to assure that sufficient forces would survive in all circumstances to deter any Soviet preemptive at- tack. The Soviet Union, particularly after the Cuban missile crisis, moved to develop a comparable, survivable strategic force. It placed much greater relative emphasis on land-based missiles, which with the missile accuracies then available were thought to be survivable in hard- ened silos. Despite its continued quantitative and qualitative advan- tage during this period, the United States decided that meaningful superiority could not be maintained against a determined Soviet adver- sary. It concluded that the real measure of strategic forces was the ability to achieve "assured destruction" of the enemy by inflicting un- acceptable damage on the other side after absorbing the worst credible preemptive attack. The Soviet Union had a similar capability that the United States could not defend against, and it was apparent the Soviet Union would not give up this capability. Thus emerged the recognition in this country, and presumably in the Soviet Union as well, that the underlying strategic reality was one of mutual assured destruction, which some soon identified and acclaimed as MAD. During this period, consideration was given to supplementing the U.S. strategic posture with a major defense component, initially a na- tionwide civil defense program and then a ballistic missile defense sys- tem. On the basis ofthis experience, a widely teased technical consensus emerged that it would not be possible for such systems to overcome the Soviet ability to inflict assured destruction on U.S. society. Neverthe- less, the United States began developing multiple independently targetable reentry vehicles, in large part to assure that U.S. missile forces could overwhelm any ABM system that the Soviet Union might deploy. In the 1970s the concept of assured destruction was formalized by the SALT ~ ABM Treaty' which prohibited efforts to achieve a nationwide ballistic missile defense system. At the same time, the concept of deter-

14 NUCLEAR ARMS CONTROL rence was extended to encompass other nuclear options. Reacting to NATO concerns about the credibility of the U.S. nuclear deterrent for a conventional Soviet attack on Europe, the Nixon and Ford administra- tions emphasized the importance of counterforce capabilities that would allow more limited nuclear options. It had always been techni- cally possible to launch only a fraction of the total U.S. strategic force. This approach was reaffirmed in the latter part of the Carter Adminis- tration in its so-called countervailing strategy. This strategy empha- sized the importance of flexible options and survivable command and control to assure deterrence against a wide range of threats. In a sense, this definition of extended deterrence simply made public policies and plans that had already existed for a Tong time. The approach to strategy and arms control during the 1970s was also characterized in both the United States and the Soviet Union by accep- tance of the fact that a rough "parity" existed between the two sides when all of the asymmetries in their strategic forces were taken into account, and that meaningful superiority was not attainable. After calling for superiority in his campaign, President Nixon called for a policy of "sufficiency." This essentially meant maintaining the level of forces necessary to assure deterrence, with no advantage accruing to the Soviet Union if it undertook a preemptive first strike, and maintain- ing "essential equivalence" in perceived forces so there would be no appearance of inferiority. The Nixon, Ford, and Carter administrations based their approaches to strategic procurement and arms control on this approach to the strategic balance. The SALT ~ Interim Agreement sought to cap the massive buildup in Soviet strategic forces that had begun in the mid-1960s. The SALT IT Treaty formalized the status of parity between the two sides by establishing equal aggregate ceilings on strategic delivery systems and a series of equal subceilings on vari- ous components of the strategic forces. In spite of these major arms control agreements, the 1970s saw a major buildup in potentially destabilizing U.S. and Soviet strategic forces. In the first half of the decade the United States deployed MIRVed warheads on a large portion of its land-based and sea-based strategic missiles; in the second half of the decade the United States developed Tong-range high-accuracy cruise missiles that essentially permitted the "MIRVing" of the strategic bomber force with air-launched cruise mis- siles. This upgrading of the existing strategic bomber force assured that its weapons could penetrate the extensive Soviet air defenses. For its part, the Soviet Union in the first half of the 1970s completed the lLarge-scaTe strategic buildup started in the mid-1960s. In the second half of the decade it moved rapidly to introduce MIRVs on its land- and sea-based strategic missiles. The impressively high accuracy of the first

OVER VIEW 15 generation of Soviet land-based MIRVs, which almost matched that of comparable U.S. missiles, implied a high kill probability against U.S. fixed missile launchers. These developments concentrated an even larger fraction of the effective Soviet strategic power on land-based missiles, which were particularly destabilizing because of the threat they posed to U.S. fixed targets and because of their potential vuInera- bility to U.S. attack. The question remains how much larger and more threatening these forces might have grown without the re- straints of SALT ~ and SALT IT. Certainly, both sides were capable of building considerably larger and more threatening forces during this period. In the 1980s the Reagan Administration has taken the position that the Soviet Union has achieved an unacceptable "margin of superiority." This advantage must be met by a major buildup of U.S. strategic forces, according to the administration, and must be taken into account in any future strategic arms agreements. Initially the administration empha- sized a "window of vulnerability" caused by the threat to U.S. land- based missiles posed by Soviet land-based missiles. The U.S. position in the START negotiations has been based on these assertions of Soviet strategic superiority and U.S. vulnerability caused by Soviet land- based missiles. The Soviet Union has insisted that a strategic parity continues to exist between the two sides. Even as it began to build up its strategic forces, the United States further broadened the concept of extended deterrence to emphasize the capability to conduct nuclear war fighting missions, including the capability to wage protracted general nuclear war. On March 23, 1983, President Reagan foreshadowed a fundamental change in the strategic doctrine that had prevailed in the previous two decades. He deplored the concept of deterrence based on assured de- struction and called for a major scientific effort to develop an effective nationwide ballistic missile defense that could ultimately eliminate the strategic role of nuclear weapons. This approach, which has been widely challenged on technical, military, and arms control grounds, would re- orient the longstanding U.S. "offense-dominated" nuclear strategy to a "defense-dominated" strategy. It remains to be seen how this radical new approach will in fact affect the United States' strategic doctrine and posture and the U.S. position on past and future arms control com- mitments and proposals. OTHER NUCLEAR POWERS The already complex problem of strategic asymmetries between the United States and the Soviet Union is further complicated by the exis-

16 NUCLEAR ARMS CONTROL fence and different perceptions of British, French, and Chinese nuclear forces. From the U.S. perspective these forces have consistently been considered separate from the U.S.-Soviet strategic balance. The United States argues that British and French forces were designed to provide an independent minimum deterrent against Soviet nuclear attack on those countries, that French nuclear forces have no commitment to NATO, and that the People's Republic of China, with no military associ- ation with the United States, has no role in the U.S.-Soviet strategic balance. From its perspective the Soviet Union must deal with the prospect of facing the British, French, and Chinese nuclear forces in a general nuclear war with the United States, and must size its own strategic forces against the combined threat. At present the strategic forces ofthe other nuclear powers are very small compared with the vast U.S. and Soviet strategic arsenals. In a general war these forces would be incre- mentally insignificant. Alone, however, they would be capable of inflict- ing tremendous damage against urban targets. The United Kingdom now has four ballistic missile submarines with 64 missiles. France has five ballistic missile submarines with 80 missiles as well as a small number of land-based ballistic missiles capable of reaching the Soviet Union. It is estimated that the Chinese may have a few hundred nuclear weapons capable of striking Soviet targets. By the mid-199Os, however, the situation could be very different. If the United Kingdom goes ahead with plans to equip its submarines with Trident IT missiles and France completes plans to MIRV its missile force, their combined strategic nuclear forces could approach 2,000 warheads. British and French nuclear forces were a central issue in the SALT negotiations. They were formally excluded from the agreement, but they appear to be compensated for by the higher levels of ballistic mis- sile submarines and submarine-launched ballistic missiles permitted the Soviet Union. In SALT IT the problem was resolved at Vladivostok when President L.eonid Brezhnev dropped the Soviet position that for- ward-based systems threatening the Soviet Union, including British and French forces, must be included in the agreement in return for President Ford's dropping the U.S. demand that the number of Soviet heavy missiles be substantially reduced. In the INF negotiations this issue has become the fundamental point of difference between the two sides. The Soviet Union has insisted that, even if the United States reduced its deployment of Pershing TIs and ground-launched cruise mis- siles to zero, the Soviet Union would not reduce its SS-20 warheads within range of Europe below the level of the combined British and French strategic nuclear forces.

OVERVIEW VERIFICATION 17 Given the status of U.S.-Soviet relations, an arms control agreement that affects vital U.S. security interests will not be acceptable unless it is possible to determine with some level of confidence that the Soviet Union is in fact honoring it. Since the systems to monitor compliance can never guarantee absolute verification, the question becomes, How much verification does a particular agreement require? The "rule of reason" standard that legislation governing the arms control process has established is that an agreement must be subject to "adequate" verification to be acceptable. While this standard is vague, it under- scores both the requirement for verification and the fact that verif~ca- tion cannot, and need not, be absolute. In the case of the SALT agreements, the government interpreted adequate verification to be the ability to determine with high confidence compliance with treaty provisions to the extent necessary to safeguard national security and to detect significant violations in time to permit an appropriate response. In meeting this standard, one would also expect to detect with varying levels of confidence a much broader spectrum of less significant viola- tions. The standard of adequate verification lends itselfto widely differ- ing interpretations of the verification required for a particular agreement. The Reagan Administration has taken the position that SALT IT did not meet its standard of verification and has implied that much more severe verification standards would be applied to its START proposals. It has been suggested that the U.S. START proposals would call for extensive use of cooperative measures and on-site inspection to improve verification capabilities. How fundamental a change may be involved and its actual effect on verification can only be judged by examining the specific START verification proposals, which have not yet been revealed by the administration. Verification has always been associated with disarmament and arms control proposals. For a long time it seemed to provide an almost impen- etrable barrier to progress in the field. President Eisenhower's proposal in the mid-1950s for open skies by means of aircraft reconnaissance and other highly intrusive inspection proposals had little prospect at that time of being accepted by a closed Soviet society and would probably not have been well received by many in the United States. In the 1960s reconnaissance satellites created a technological revolution in the pos- sibilities of verification without highly intrusive measures. The SALT agreements established satellite monitoring as internationally ac- cepted means of verification. Satellite monitoring systems which to-

18 NUCLEAR ARMS CONTROL "ether with any technical systems, such as radars and radio antennas, located outside the country under surveillance are now designated as National Technical Means (NTM) have become the key to the verifica- tion of arms control proposals. There are, however, proposals that clearly cannot be adequately veri- f~ed by National Technical Means alone. In some cases the capabilities of National Technical Means can be extended by agreements providing for cooperative measures that facilitate the monitoring process. In cer- tain cases, intrusive on-site inspection may still be the only technique available to provide adequate confidence, or any information at all, on certain activities. One example is the safeguarding of operating nuclear power facilities against diversions of materials to nuclear weapon pro- duction. On-site inspection is not a panacea for all verification prob- lems. In some cases, such as the verification of the MIRV ceilings in SALT IT, even very intrusive on-site inspection by itself would have been much less effective than National Technical Means used in con- junction with the counting rules for launchers. In this and other ex- tremely intrusive cases, it is by no means clear that on-site inspection would have been acceptable to the United States in the very unlikely event that the Soviet Union agreed to it. RECORD OF COMPLIANCE Closely coupled with the verification issue is the record of compliance with existing agreements and the question of what can and should be done to enforce agreements. In presenting SALT IT to the Senate, the Carter Administration contended that the record of compliance with the SALT ~ agreements had been good and presented extensive informa- tion to document its case. While a number of questionable Soviet activi- ties had been detected and presented to the joint Standing Consultative Commission, which SALT ~ had created for this purpose, the U.S. gov- ernment concluded that every case had been satisfactorily resolved. Some critics of SALT IT challenged these conclusions. In response to a Senate request, President Reagan submitted a report to Congress on January 23, 1984, stating that "The United States Gov- ernment has determined that the Soviet Union is violating the Geneva Protocol on Chemical Weapons, the Biological Weapons Convention, the Helsinki Final Act, and two provisions of SALT 1:~: telemetry encryption and a rule concerning ICBM modernization. In addition, we have deter- mined that the Soviet Union has almost certainly violated the ABM Treaty, probably violated the SALT IT limit on new types, probably violated the SS-16 deployment prohibition of SALT II, and is likely to

OVERVIEW 19 have violated the nuclear testing yield limit of the Threshold Test Ban Treaty." The Soviet Union denied all of the charges and made its own charges of U.S. violations of existing agreements. Domestic critics have questioned some of the U.S. charges and have noted that the charges were considerably weakened by the assertion of the U.S. government that SALT IT established only "political" and not "legal" obligations since the United States did not intend to ratify the treaty. Whatever the correct explanation of these activities, the President's report to the Senate that the Soviet Union has violated formal agree- ments will make it much more difficult to cite past experience as evi- dence that the Soviet Union can be expected to comply with the provisions of future agreements. The U.S. charges also raise the ques- tion of how to deal with apparent violations or possible violations. In the past these problems were dealt with privately, with both sides seeking an explanation or mutually acceptable solution to preserve the integ- rity of the agreement. The question now is, Will a policy drawing public attention to the charges put pressure on the Soviet Union to comply with agreements, or will it weaken domestic confidence in arms control and Soviet willingness to participate constructively in a continuing discussion of compliance problems? POLITICAL OR MILITARY "LINKAGE" A fundamental issue in the development and negotiation of arms control agreements is the extent to which they should be "linked" to other political or military considerations. Perhaps the issue can be more realistically stated as the extent to which arms control negotiations can be isolated from other political and military activities. In the past the United States has sought in principle to avoid linkage in arms control negotiations with the Soviet Union. The argument has been that arms control agreements should stand on their own merits, even in times of heightened or reduced tensions. They should not be used as rewards for good behavior or withheld for bad behavior. In practice, some degree of linkage is probably inevitable in the United States, given the high political disability of arms control negotiations. A striking example of the delinkage or isolation of the arms control process from potentially disruptive events occurred when the United States mined Haiphong Harbor and bombed Hanoi the day after Prime Minister Alexei Kosygin's visit to that city at a critical juncture in the SALT ~ negotiations. To the surprise of the U.S. delegation, the Soviet delegation did not walk out of the negotiations or even protest the action. In contrast, after the Soviet invasion of Afghanistan at the end of

20 NUCLEAR ARMS CONTROL 1979, President Carter asked the Senate to discontinue the SALT IT ratification process. This action reflected both the President's desire to link ratification of the treaty to acceptable Soviet behavior in an unre- lated area and his recognition of the linkage of the upcoming Senate vote on ratification to the adverse public reaction to Soviet behavior in Afghanistan. The recently terminated INF negotiation is the most obvious example of direct linkage of the arms control process to external objectives. Whatever the negotiating intentions of the two sides, it became clear as the negotiation was conducted increasingly in the open that both sides' immediate interest was the political impact of the negotiation on the impending U.S. deployment of Pershing Its and ground-launched cruise missiles in NATO. THE NEGOTIATING PROCESS It is not particularly difficult to design nuclear arms control proposals that a broad political spectrum of American citizens would judge to be unambiguously advantageous to U.S. security interests. It is a much more difficult task to design and negotiate arms control agreements that the political and military establishments of both the United States and the Soviet Union see as mutually advantageous. A powerful sover- eign state will clearly not be persuaded or coerced to accept an agree- ment that it judges to be contrary to its overall security interests. Although underlying motives and concerns may differ, there must be a significant area of common interest to make the negotiation of an arms control agreement possible. A central issue in arms control negotiations is the extent to which the basic proposals should be "negotiable." A negotiation is a bargaining process between or among potential adversaries, and opening positions are seldom final positions. While a negotiable proposal may be formu- lated from the advocate's perspective, it is directed at perceived mutual objectives within a framework that can lead to a formulation acceptable to both parties. This can still be a very slow and difficult process. The SALT IT negotiations extended over seven years, even though the basic objectives and framework were agreed on relatively early in the process. An alternative approach that was openly favored at the outset of the Reagan Administration was to design proposals to optimize perceived legitimate U.S. interests without regard to their negotiability from the Soviet perspective. The administration argued that if the U.S. positions were right the Soviet Union might be persuaded; if the Soviet Union

OVERVIEW 21 could not be persuaded' the United States would be in the strongest bargaining position in dealing with Soviet counterproposals. The con- cept of negotiability was rejected as a criterion in judging the accept- ability of arms control proposals. Whatever form proposals take, there are obvious advantages in com- ing to the negotiating table in a strong position. In this case, strength is measured not just in military forces but also in domestic and interna- tional political support. At the same time, experience indicates that the prospects for agreement are poor if either side has, or is perceived to have, real superiority in the military area under negotiation. The Reagan Administration initially emphasized that the United States would have to undertake a major arms buildup to be able to negotiate with the Soviet Union from a position of strength. To what extent the initiation, as opposed to the actual deployment, of new programs is judged by the administration to have met this criterion is not clear. The notion that one must "arm to parley" is not new, and critics would characterize it as simply the next phase of the arms race presented in a more palatable form. Another controversial issue in the approach to the negotiating pro- cess is the value of"bargaining chips." Military assets that can be traded as bargaining chips against present or future components of an adversary's forces can in theory play a useful role in a negotiation. To be really effective negotiating tools, such bargaining chips must have real military significance. Militarily significant systems are prone to take on a life of their own, however, and to be judged so valuable as to be nonnegotiable. In SALT I, some may have considered the new MIRV technology as a powerful bargaining chip, but it soon became clear that it was not negotiable by either side. In SALT IT and START, the MX program was frequently supported as a critical bargaining chip, but it has never really been used for this purpose. On the other hand, it has been argued that U.S. plans in the late 1960s and early 1970s to deploy ballistic missile defense systems contributed to the successful negotia- tion ofthe ABM Treaty in 1972. At the other extreme, there is the question of whether unilateral restraint can contribute to the successful negotiation of an agreement. At the beginning of the trilateral negotiation for a comprehensive nu- clear test ban in 195S, President Eisenhower's declaration of a one-year moratorium on nuclear testing undoubtedly lent an air of seriousness and urgency to the first real effort at negotiated arms control. Critics would note, however, that Eisenhower unilaterally terminated the mor- atorium at the end of 1959 and that a comprehensive test ban was not achieved. Currently, the Soviet Union has declared a moratorium on

22 NUCLEAR ARMS CONTROL the testing and deployment of anti-satellite weapon systems. Congress has also passed legislation, over administration objections, mandating a moratorium on the full testing of anti-satellite systems while efforts are pursued to reopen the U.S.-Soviet negotiations on such systems. The question remains whether such actions accelerate the negotiating pro- cess and point it in a favorable direction or weaken negotiating leverage to obtain the best agreement. DOMESTIC POLITICAL ACCEPTABILITY The extent of public and political support for arms control agreements is a serious issue underlying the arms control process. Public support for arms control has been closely linked with the varying fortunes of the U.S.-Soviet political relationship. These changing public attitudes are coupled with the unique requirement of the U.S. Constitution for a favorable vote of two thirds of the Senate to "advise and consent" on treaty ratification. The remarkable changes in public and congressional attitudes are illustrated by the different reactions to SALT ~ and SALT IT. In 1972 the U.S. Senate approved both the SALT ~ ABM Treaty and the SALT ~ Interim Agreement by separate votes of SS to 2. In 1979, before the Soviet invasion of Afghanistan, it was judged a close call whether SALT IT would receive the necessary two-thirds vote in the Senate. After the Afghanistan invasion, all observers agreed that it would be impossible to obtain Senate approval of the treaty at that time. This was the politi- cal reality even though SALT TI did not raise basic doctrinal issues as did the ABM Treaty and appeared to answer many of the criticisms of the earlier SALT ~ Interim Agreement. Despite the intense public interest in arms control today, a national consensus on this issue clearly does not exist. For its part, the Congress has increasingly shown its independence on issues of national security and foreign policy, which have previously been largely delegated to the executive branch. Consequently, arms control proposals must be judged not only on their negotiability with the Soviet Union or other nations but also on their acceptability within the complex political process of the United States. SPECIFIC PROPOSALS This chapter has outlined the broad range of general issues underly- ing the nuclear arms debate today. The debate itself can only be under- stood and assessed in terms of specific proposals. The following chapters

OVERVIEW 23 present the background and issues relating to each of the principal current agreements and proposals directed at nuclear arms control. In each case the issues are addressed from the point of view of the various protagonists in the debate. It is hoped that this approach will help readers arrive at their own conclusions on these matters of such critical importance to the United States and the world at large.

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This nontechnical overview of developments in nuclear arms control describes how the United States and the Soviet Union arrived at their present positions—and where they might go from here. According to Foreign Affairs, "This book is proof that the complexities of arms control can be successfully explained in a nontechnical, and even more importantly, nonpartisan manner....It presents the key issues in a clear, thorough, and remarkably up-to-date way....Strongly recommended as a primary source for classroom and public discussions."

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