Our policies for preventing nuclear war, mercifully, have never been tested to the point of failure. This cannot be said of our policies that have sought to reverse, or at least to halt, the expansion of nuclear arsenals threatening our annihilation. For more than two decades now, the United States, using both diplomacy and self-restraint, has tried—and failed—to halt the nuclear arms competition with the Soviet Union.

The most important reason for seeking to manage and control the nuclear arms competition is to reduce the risk of nuclear war. The U.S. pursuit of these linked objectives, however, has been under the spell of a particular theory from the mid-1960s until recently. This theory holds that "the two sides" can limit or reduce their nuclear weaponry if, and only if, they both consent to leave their territory totally vulnerable to each other’s nuclear attack. Such consensual vulnerability constitutes "strategic stability," according to the theory, and is the best, if not the only, way to prevent nuclear war for the indefinite future.

In the real world, nuclear forces are built and managed not by two indistinguishable "sides," but by very distinct governments and military organizations. These, in turn, are run by people, people who are ignorant of many facts, people who can be gripped by anger or fear, people who make mistakes—sometimes dreadful mistakes.

The intellectual poverty of the consensual vulnerability theory accounts for much of the current opposition to strategic defense. Of course, like most theories that gain throngs of adherents, this theory contains a kernel of truth. Up to a point, the nuclear age has led to "two sides" mutually vulnerable to each other’s retaliation. So any military expert may say some valid things about mutual nuclear vulnerability without considering how governments really function, or how people think and act. So too, any surveyor can measure a plot of land without considering the shape of the earth. But we cannot navigate to a distant haven if we assume the earth is flat.

II

Even the purely technical dimension of the nuclear age is often oversimplified, as if to fit a flat-earth theory. Today’s opponents of strategic defense argue that their concept—"two sides" agreeing to a stable relationship of consensual vulnerability—reflects not a choice of doctrine but an inescapable technological fact. The mutual threat of assured destruction as the guarantor of peace, they say, is unchangeable because nuclear weapons cannot be disinvented.

Although nuclear weapons cannot be disinvented, other things are being invented. To say that the immense destructiveness of nuclear weapons makes the nuclear era unique is but a partial truth. As we look back in human history, to be sure, nuclear arms represent a unique change in the meaning of war and peace. For the future, however, we must expect other changes of perhaps comparable scope and consequence. Technology does not stand still, nor stay put in a few countries. And no heavenly law operates in this world to constrict the results of technological advances to "two sides."

It is important, therefore, to separate technological facts from doctrinal fictions. It is a fact that modern technology provides means that could be used to destroy people, wealth and even parts of nature with a totally unprecedented speed, intensity and magnitude. It is fiction, however, that the nuclear arsenals of the two superpowers are the only such means we need to be concerned about. It is a fact that other devices for mass destruction, existing or yet to be invented, could be delivered to an intended target in ways that are difficult, or perhaps too costly, to prevent. To conclude, however, that the only practical way to protect against destruction is to threaten retaliation in kind reflects not a permanent fact of technology but a choice of doctrine.

The sequence in which science presents governments with possibilities for new devices of destruction or new means to counter them is a vagary of history. Imagine that early in this century the development of science had taken a different turn. Biology and genetic engineering might have made dramatic advances, instead of the great progress in physics that then occurred. As a result, a different "Manhattan Project" in World War II could have produced a radically new biological weapon, exploiting the destructive potential of genetic engineering that people have begun to worry about today. Such a weapon could be far more efficient for causing mass destruction than the biological agents that the United States eliminated in the early 1970s, in compliance with the biological weapons treaty. That treaty, we recall, permits defensive measures but prohibits testing and stockpiling of offensive biological weapons—the reverse logic of the Anti-Ballistic Missile (ABM) Treaty.

Today’s opponents of ballistic missile defenses often argue that such defenses are useless, since the "other side" could always smuggle nuclear bombs into our cities—the suitcase bomb. Hence, they conclude, we must rely exclusively on our ability to retaliate. None of these opponents of defense, surely, would choose to ban defenses and rely only on retaliation in kind if the "other side" developed powerful new biological weapons—whether or not these could be delivered in suitcases.

Yes, ballistic missile defenses could be circumvented. There are many ways to sneak a nuclear explosive into a city. Some day such an act might be attempted by a terrorist organization, or by a nuclear power that pursues irrational terrorist ends. A U.S.-Soviet relationship of consensual vulnerability would afford absolutely no protection against such a disaster. On the contrary, it might make it more likely or even aggravate its consequences.

Thus, it is not the destructiveness of a particular technology, but vagaries of both technological development and of American strategic thought, that have led to the excessive emphasis on retaliation and to the neglect of defenses in the current strategic posture of the United States. The notion of a stable strategic relationship based on the acceptance of mutual vulnerability reflects not a state of nature but a state of mind.

III

Whenever the proponents of a theory resist new facts while attacking all alternative explanations as heresies, that theory turns into dogma. At that point, the proponents often try to buttress their case by distorting history. Critics of President Reagan’s initiative on strategic defense have charged that his proposed defenses would upset a stable relationship of mutual deterrence that has obtained throughout the nuclear era.

But this stable equilibrium of "two sides" defenselessly poised for mutual assured destruction has never existed.

For the first five years of the nuclear era, there was no stable balance of nuclear forces at all—the United States had a monopoly. For the next 15 years, neither the United States nor the Soviet Union eschewed defenses against nuclear attack in pursuit of a mutual vulnerability theory. In the 1950s, the United States spent about two-thirds as much on air defenses as on nuclear offensive forces, some $200 billion in ten years (in today’s dollars). In 1960, the United States actually allocated more to its defenses against Soviet nuclear attack than to its nuclear offensive forces.

Only in the 1960s did the theorized "stable" balance of consensual vulnerability become a partial reality, in the very limited sense of shaping U.S. force planning and U.S. arms control policy. Beholden to the "flat earth" theory, we saw to it that we would be proven right in our own garden. For two decades we shrank our budget for nuclear offensive forces nearly every year. We reduced expenditures on our defenses against nuclear attack drastically, and after 1970, we cut them practically to zero. And, most dangerous of all, we permitted our intelligence projections for Soviet forces to become warped by our own dogma. In particular, from the mid-1960s to the early 1970s, we misled ourselves by the mistaken forecast that the Soviet Union, in light of our self-restraint, would not want to overtake us in nuclear offensive forces, much less seek a capability for destroying most of our deterrent strength.

The 1972 treaty curbing ballistic missile defense became the apotheosis of this belief. In the American view, it was meant to seal a Faustian bargain with the devil of nuclear destructiveness. By the terms of this bargain, both sides had to guarantee their own devastation on a possible Judgment Day, when one side, having been attacked by the other, would want to avenge this attack. Thus, Judgment Day would never dawn. In American eyes, the implied bargain consisted of two parts: both sides would abstain from defenses that could destroy the opponent’s revenge forces after they are launched; and both sides would abstain from the kind of offensive capabilities that could destroy the opponent’s revenge forces before they are launched. In the jargon, the former are called "active defenses," the latter, "counterforce" capabilities.

Only the United States kept one part of this two-part bargain. Only the United States gave up on active defenses, against aircraft as well as against ballistic missiles. The Soviet Union, by contrast, has spent slightly more on active defenses since the signing of the ABM Treaty than on its nuclear offensive forces. Some of this effort went into a vigorous program for ballistic missile defense (both deployment of the treaty-permitted Moscow system, and the development of future systems); the bulk of it went into air defense.

The United States initially intended to keep the counterforce part of the bargain. From 1970 to 1972, the U.S. Congress voted against improving the accuracy of our missiles in order to deny ourselves the ability to destroy Soviet missiles in their silos. But the Soviet Union continued its expensive buildup of nuclear forces, including enhanced versions of the SS-18 and SS-19 intercontinental ballistic missiles, contrary to a policy of eschewing counterforce. So, by the end of the last decade, as the Soviet buildup in counterforce capability continued unabated, we felt compelled to respond in kind. As the President’s Commission on Strategic Forces (the Scowcroft commission) put it in 1983: ". . . we cannot safely permit a situation to continue wherein the Soviets have the capability promptly to destroy a range of hardened military targets and we do not." Clearly, our arms control efforts had failed to halt competition in counterforce capabilities.

Thus came to naught the leading concept for strategic arms control that reigned in the United States from the mid-1960s until recently. By now, this story has often been told. Yet many Americans and Europeans still pine for the Faustian bargain that they believe the ABM Treaty had sealed. In a triumph of hope over experience, they want to try again.

IV

It is important to understand the essence of these painful lessons. The strategic world does not consist of "two sides," each willing to be locked into a symmetry of utter vulnerability. Even though we tried to conform to this dogma, the "other side," that is to say the real Soviet leaders and their real military advisers, did not. These men made every effort to reduce the vulnerability of their country—and especially of themselves. They ordered the construction of a great many hardened command posts, located well away from cities, for military commanders and officials at all levels of the government and Communist Party. They maintained a vigorous effort to improve their air defenses and develop missile defenses. And, above all, they deployed missiles increasingly capable of destroying our nuclear forces, thus equipping themselves to eliminate the cause, the very source, of their own vulnerability.

Why didn’t the Soviet leaders act in accordance with our theory? Perhaps they did not want to entrust forever the future of Soviet communism and the Soviet empire to the rationality of American leadership. Perhaps they did not want to rely on the discipline and technology of the American military forever to prevent a cataclysmic accident. Perhaps, in their eyes, American policy seemed incoherent—and, hence, made them skeptical of our intent—since it combined the American doctrine of "stable" mutual vulnerability with the NATO deterrence policy that includes the threat of using nuclear weapons first in response to a massive conventional attack. But it is also possible that they saw in the absence of U.S. ballistic missile defense an invitation to acquire the missilery capable of destroying the U.S land-based deterrent.

Those who remain opposed to strategic defense argue that missile defenses would merely stimulate the "action-reaction cycle of the arms race." The Soviet leaders, they maintain, would feel compelled to thwart our active defenses. Up to a point, to be sure, this may be a valid prediction. For a short stretch of our voyage, it is safe to assume the earth is flat. For a while, yes, the Soviet leaders undoubtedly would try to thwart our active defenses, much as they are trying to thwart passive defenses such as hardening and mobility that protect our deterrent today. By increasing the numbers, accuracy and destructive power of their missile warheads, they aim to overwhelm our hardened missile silos; by expanding their air defenses, they try to counter the survivability of our bombers; by stepping up their anti-submarine program, they try to negate the protective mobility and quietness of our nuclear missile submarines.

Here is a classic action-reaction cycle in armaments. Ought the United States to desist from improving these protective measures for its deterrent forces? Would anyone advocate such U.S. self-restraint—say, a halt in the hardening of our missile silos or in maintaining the protective elusiveness of our submarines—"to slow down the arms race"? In this country, most opponents of strategic defenses would not endorse such an idea. On the contrary, they postulate a stubborn determination on each side to protect its retaliatory forces. Yet their dogma excludes the possibility that one side might have, as well, a stubborn determination to protect its homeland.

Would the Soviet leaders, in fact, augment their offensive missile capabilities in order to thwart our defenses? This will depend on the ability of our defensive systems to impose costs and difficulties sufficient to dissuade them from doing so. Also, very importantly, it will depend on our presenting to the Soviet leaders alternatives for their nuclear policy that they can find acceptable. President Reagan’s initiative seeks to meet both these conditions. It offers the Soviet leaders a new strategic relationship with the United States that will better meet their fundamental security requirements. And it ushers in new technologies for defense that hold the promise of making counter-measures unattractively costly.

A case in point here may be the history of the Soviet bomber program. When we invested heavily in air defenses in the late 1950s, the Soviet Union ceased building new bombers and instead shifted to ballistic missiles. But, when it became clear that we had given up on air defenses, the Soviets again invested in the development and then the production of a new strategic bomber. They decided to build new vehicles to take advantage of the freeway we opened for their bombers.

By analogy, if we began to close the freeway in space that we have preserved for ballistic missiles, the Soviet military might stop investing in new ballistic missiles and instead rely on new bombers and cruise missiles. That in itself would be a great gain. Bombers and cruise missiles, compared with ballistic missiles, are less suited for surprise attack because of their longer time of travel. And bombers are safer as deterrent forces since, by taking to the air, they can be made nearly invulnerable in an alert, yet could safely return to their bases should the warning be false. Also, using in part the same technologies and systems, air defenses could later complement our ballistic missile defenses.

In sum, throughout the nuclear era, all the evidence shows that the U.S.-Soviet strategic relationship never conformed to the theory of stable consensual vulnerability—either before or since the ABM Treaty. Furthermore, contrary to that theory, the Soviet government has not designed and financed its vast nuclear buildup just to maintain forces for destroying American society. Instead, by acquiring active defenses and counter-force capabilities, it has shown its determination to reduce Soviet vulnerability rather than depend exclusively on such a threat of revenge.

V

Unable to achieve a stable equilibrium of vulnerability between us and the Soviet Union in the past, are we likely to achieve such a strategic order in the future? Compelling reasons make this a most improbable outcome.

If we put the flesh and bones of real governments on the abstraction of "two sides," and if we recognize that these governments must function in the real world of many powers—of allies, of captive nations, of friends and foes—then we can readily see why such a two-sided equilibrium of mutual vulnerability is a relationship that cannot remain stable.

To begin with, the makers of Soviet foreign policy take a long-term view. Even if they were prepared to trust the U.S. government always to play the role of the reliable partner in such an equilibrium, they would feel it essential to take account of other nuclear powers, present or future. The planners in Moscow surely recognize that, despite the astonishingly successful American-Soviet cooperation in curbing the spread of nuclear weapons, the capacity to manufacture nuclear explosives will continue to spread to additional countries. They must be aware, for example, that they once helped China to acquire a nuclear capability and are now facing a slowly expanding strategic nuclear force across the world’s longest border.

But, quite apart from the fact that the arena of nuclear powers does not consist of only two sides, there is a more fundamental reason why we should not expect the Soviet leadership to settle for the strategic order of consensual vulnerability. Like oil and water, the two ingredients in this order will always separate: the accord on a stable equilibrium of mutual restraint is psychologically incompatible with the constant threat of reciprocal annihilation. The first ingredient of this mixture represents the best in international relations: a continued willingness to cooperate in restraining one’s own military power, coupled with a serene reliance on the opponent’s prudence and his common sense. The second ingredient of the mixture represents the worst in international relations: an endless effort to maintain forces that are constantly ready to annihilate the opponent, coupled with an unremitting determination to deny him escape from this grip of terror.

The believers in the dogma of a stable, mutually agreed vulnerability fail to appreciate the dynamic of this incompatibility. Their vaunted strategic order is unstable at its very core. We cannot keep the balance of mutual threats of mass destruction from ceaselessly tilting. Yes, we can try to adjust this quivering balance, year after year, augmenting our offensive nuclear forces, substituting more effective or more survivable nuclear arms for older ones, in order to defeat the inevitable Soviet attempts to reduce the magnitude of the American nuclear threat to themselves. This has been our policy in past decades.

Today’s critics of strategic defense argue that the Soviet rulers would never accept a strategic order in which the United States and its allies were no longer vulnerable to nuclear mass destruction, even if these rulers could acquire a similarly effective defense of their own homeland. Yet the critics firmly believe that these same Soviet rulers, whom they view as hellbent on maintaining their threat of our destruction, will forever nestle down with us in an equilibrium of mutual vulnerability. By accepting such an equilibrium, the Soviet rulers would have to accept indefinitely a future where any American president, or (in their eyes) perhaps even "some American general," could unleash the engines that would destroy the Soviet Union. To the men in the Kremlin, such a world cannot look like a place of stability. It cannot be the chosen destination of Soviet policy. As Soviet Foreign Minister Andrei Gromyko put it in 1962: ". . . to base the policy of states on a feeling of universal fear would be tantamount to keeping the world in a permanent state of feverish tension and a hysteria anticipating war. In such an atmosphere, each state would fear that the other side would lose its nerve and fire the first shot." Contrary to Gromyko’s protestations today, the 1972 ABM Treaty did not convert the Soviet government to a strategic order of consensual vulnerability; Soviet investments in offensive and defensive systems speak louder than current denials.

VI

One cannot address the future of our nuclear strategy without considering the role of American nuclear weapons in NATO’s defense policy. Ever since the Yalta agreement 40 years ago, a major objective of the United States has been to prevent Soviet domination of Western Europe. This imperative has confronted a stubborn problem: for an attack on Western Europe, the Red Army could amass manpower and firepower that always seemed superior to the forces the West European nations could muster. The creation of the Atlantic alliance provided but a partial solution. Even the combined forces of the alliance, the allied governments have held, could not be kept at a strength sufficient to defeat a massive and sustained Soviet attack in a conventional war.

Hence it has always been agreed within the alliance that nuclear weapons must play an essential role, whether in deterring conventional attack, or in coping with such an attack should deterrence fail. This role, in turn, has exerted a pervasive effect on the development of our nuclear forces, strategy and arms control policy—an effect far greater than is often realized. Deterring or responding to a conventional invasion of Western Europe was the primary mission of the U.S. Strategic Air Command well into the 1950s, and throughout the 1950s the United States opposed negotiating limits on its nuclear forces without a reduction in the conventional threat to Europe. It has proven difficult, however, to agree on a single, coherent concept for this role of nuclear arms in protecting allies. The political leaders, defense officials and military staffs of the Atlantic alliance have shaped and reshaped, time after time, several strategic concepts.

The initial concept exploited the American advantage in nuclear weapons. During the short-lived American monopoly, the application of this concept, in theory, seemed simple. In the event the Red Army invaded Western Europe, the U.S. Air Force would drop atomic bombs on targets in the Soviet Union. Actually, as seen from Washington at that time, it was far from certain whether U.S. nuclear forces would have been powerful enough to inflict a decisive military defeat on the Soviet Union. And later, when the United States had acquired a nuclear arsenal and delivery systems able to destroy the Soviet Union as a military power, it could not be certain of escaping grievous damage at home from Soviet retaliation. The Eisenhower Administration agonized long and hard over this dangerous dilemma.

So a second concept was born, which envisioned using nuclear weapons on the battlefield, not to retaliate, but to repel the invading divisions. This concept held to a more traditional, a more "conventional," application of military power. As Secretary of Defense Charles Wilson put it in 1957, "The smaller atomic weapons, the tactical weapons, in a sense have now become conventional weapons. . . ." As long as the United States enjoyed an effective advantage in nuclear forces, these two concepts could lend coherence to the overall strategy. In the jargon of the nuclear theorists, we enjoyed "escalation dominance": we thought we had more, or more effective, tactical nuclear weapons, so we could expect to deter, or if necessary defeat, a Soviet invasion by using tactical nuclear weapons; and we had superior global nuclear forces, so we could expect to deter the Soviet Union from using its intercontinental nuclear forces against us.

Today, this "escalation dominance" has been overtaken by the massive changes in nuclear arsenals. Indeed, on both sides of the Atlantic, it is no longer judged to be a solution. The United States patently has no plans to regain its former advantage in global nuclear arms, or to restore the West’s superiority in tactical nuclear arms. A few years ago, in fact, political opinion in Europe opposed even the deployment of the so-called "neutron bomb," a weapon capable of killing enemy soldiers in their tanks without destroying the nearby towns. Yet, the more these tactical nuclear weapons can destroy the intended military target without destroying what they would seek to defend, the greater would seem their credibility as a deterrent.

Despite the massive changes since the end of World War II, there is wide agreement on both sides of the Atlantic that nuclear weapons continue to contribute to the deterrence of a conventional invasion of Western Europe. This consensus comes easy. However, the concepts guiding the use of nuclear weapons should such deterrence fail are more painful to spell out. Some of Europe’s political leaders and elected representatives understandably prefer to avoid the issue. Some assert that NATO’s nuclear weapons must never be used to defeat invading Soviet divisions, but only to preclude armed aggression by threatening massive nuclear revenge. Here we meet the old problem bedeviling the theory of deterrence: the credibility of threatening an irrational act. If a conventional war ever broke out and the invading divisions pressed forward, could the act of nuclear revenge serve the national interest of any member of the alliance? If not, will the threat be credible in time of crisis?

Folly likes company. Many of those who would constrict NATO’s nuclear policy to such a threat of revenge also oppose missile defenses, clinging to the dogma of consensual vulnerability. And, to boot, they often fail to support increased conventional strength, thus leaning even more heavily on their dubious nuclear threat. By rejecting missile defenses for Europe, they would leave many critical elements of NATO’s conventional and nuclear forces vulnerable to shorter-range Soviet missiles, which—even if conventionally armed—could be accurate enough a decade hence to destroy some of NATO’s key facilities. In essence, they would rely almost exclusively on the global nuclear forces of the United States to provide the comprehensive guarantee that protects Europe.

In the long run, the force of this guarantee depends on its support by the American people. Some European opponents of missile defenses for the United States appear to believe that to assure the vulnerability of the United States somehow preserves this guarantee. This logic makes no sense. It implies that the larger the number of Americans who would be killed in a nuclear war, the more credible a decision by the U.S. president to respond to a conventional invasion of Europe by initiating nuclear war.

Now, it must be said that a free alliance of democratic nations is a very ecumenical association. Many contradictory beliefs can coexist—provided the alliance is at peace. It is in time of war, or even during a major crisis, that the coherence of the allied strategy would be put to the final test.

VII

Our democracies will have to defend themselves for the foreseeable future against the military might and political ambitions of the Soviet ruling class, still dominated by men imbued with Lenin’s totalitarian philosophy. And who can foretell whether other totalitarian powers might not emerge as major military threats to Western democracy? Against such opponents, democratic governments cannot keep up the necessary strength, decade after decade, without the continuing support of their people.

But the men and women who work and vote in our democracies have never been tested against the searing edge of nuclear war, nor have the politicians, soldiers and scientists who must dedicate themselves to sustain our military strength. Only the effects of low-yield nuclear weapons on isolated military targets can be predicted with some confidence, having been tested realistically. Much remains unknown. Sometimes a particular horror is overlooked, sometimes it is exaggerated. Possibly critical effects that might result from large-scale nuclear attacks have been discovered only by accident.

For example, in 1954, one of our thermonuclear tests in the Pacific accidentally disclosed the potential extent of radioactive fallout; the medical histories of the injured people subsequently disclosed the human consequences of fallout; a high altitude test in 1958 led to the accidental discovery of electromagnetic blackout; in the early 1970s, totally unrelated studies revealed how high-yield nuclear explosions might damage the ozone layer; and in the early 1980s, new studies opened the possibility of "nuclear winter."

Naturally, such revelations awaken those deep anxieties about nuclear war that slumber in our minds. For many people they strengthen the belief that nuclear war would mean "the end"—not just of their own lives and those of their families, but of their country and all they cherish. In various ways, therefore, the people in democracies express a strong belief that nuclear weapons cannot be used as instruments of national policy, except somehow to preclude "the end." Recent opinion polls show that close to 80 percent of respondents both in Western Europe and in the United States oppose the use of nuclear weapons if a conventional invasion of our European allies could not be repelled by non-nuclear means. A surprising number of people have lately been saying they would even oppose using nuclear weapons in response to a Soviet first use; they thus betray perhaps a touch of confusion about the intended working of deterrence.

Within Western alliances, citizens who so strongly reject almost any military use of nuclear arms can readily organize themselves to promote policies that would reduce—in their eyes—the risks of nuclear war. This is as it should be in free democracies. It is also not unexpected that the Soviet government tries to reinforce, and perhaps redirect toward its own goals, these political stirrings in the West.

What the Soviet government has recently done on this score is trifling, however, compared with what in a major crisis a Leninist or Stalinist might choose to do. Someone in control of Soviet military power and schooled in the uses of terror for political ends could lay iron hands on the deepest emotions and fears of a great many people in the West. He could make them believe that the horrors of nuclear destruction were about to become real—unless they prevailed on their leaders to make major concessions.

Even the current deployment of intermediate-range missiles in Western Europe came close to being prevented by the combined pressures of Soviet manipulation and political opinion in the West. Had one of the West European elections turned out differently, the Soviet government would have succeeded in depriving the alliance of one of the supports it sought for deterrence. Mark that this was in peacetime, when nuclear destruction seems a remote abstraction. Mark also that the pressures employed by the Soviet government were mild—merely diplomatic admonitions and some furtive propaganda operations in the West. Can we count on future Soviet leaders being so "cautious" that they would not use the hammer and anvil of nuclear terror, even in a crisis?

In the future, Stalin’s heirs, recalling the effectiveness of mass terror in the pursuit of power, may discover new ways to turn the threat of nuclear destruction into the ideal instrument for totalitarian expansion. It would serve no useful purpose here to speculate on how they might go about this. One is reminded, though, of an idea that surfaced many years ago: detonating a large nuclear weapon more or less harmlessly in the sky as a "demonstration" of one’s seriousness. (Of course, at that time the shoe was on the other foot; the idea was that the Western democracies would frighten the heirs of Stalin.) For the future, the "balance of terror" cannot favor the defense of a democratic alliance. Sooner or later, it will favor those most at ease with, those most experienced in, the systematic use of terror.

The West has long relied heavily on the creativity and inventiveness of its scientists and engineers to compensate for the Soviet advantages in territory and mobilizable manpower. But our scientists and engineers, like any professional men and women, require moral satisfaction to work creatively. It can become a demoralizing task to invent and perfect, year after year, better means for inflicting nuclear destruction—not to defend one’s country, but to revenge its destruction. The prospect of achieving strategic defense provides a new, positive motivation for our scientists and engineers who work on national security.

The danger of demoralization by relying on a strategic order of consensual vulnerability goes further and deeper. Upon an alliance of democracies, such a policy imposes a passive, almost cynical, resignation toward the possibility of an atrocity unsurpassed in human history. It offers a prospect of anxiety without relief, an intellectual legacy crippling the outlook of each new generation, a theme of desolate sadness. As Kenneth Clark observed, civilizations require confidence, "confidence in the society in which one lives, belief in its philosophy. . . ." To insist that only a rigorously preserved vulnerability will preserve us from annihilation is a credo that must corrode the confidence upon which civilizations are built.

VIII

The conclusions fall into place. We need to accomplish a long-term transformation of our nuclear strategy, the armaments serving it, and our arms control policy. To begin with, we must disenthrall ourselves of the dogma of consensual, mutual vulnerability—the notion that unrelieved vulnerability of the United States and the Soviet Union to each other’s nuclear forces is essential for halting the competition in offensive arms, and is the best guarantee against the outbreak of nuclear war.

Such a relationship never obtained in the past and it is most unlikely to come into existence in the future. Moreover, an agreed balance of mutual vulnerability would be repugnant on moral grounds. And it could in no way reduce the consequences of an accidental nuclear attack. In the long run, reliance on a balance of mutual vulnerability would favor totalitarian regimes, with a demoralizing effect on democracies.

The key now for the needed transformation is technological development to make effective defensive systems possible for the United States and our allies. The priority requirement is non-nuclear missile defenses capable of negating the military utility of a Soviet missile attack and of diminishing its destructiveness. Depending on progress in arms reductions, the missile defenses might later be complemented with air defenses. As strategic defenses make it increasingly unlikely that Soviet offensive forces can accomplish their mission, the incentive for new Soviet investment in them is reduced. We thus enhance Soviet willingness to join us in deep reductions of offensive forces.

To this end, we ought to take two complementary approaches. We should energetically seek Soviet cooperation, since it would greatly ease and speed the transformation. But we must also be prepared to persist on the harder road, where the Soviet Union would try as long as possible to overcome our defenses, and would resist meaningful reductions in offensive forces. The better prepared we are and the more capable of prevailing on the hard road, the more likely it is that the Soviet Union will join us on the easy road.

Critics of missile defenses fear that defenses could not be made leak-proof against a massive attack, that a fraction of the missiles might penetrate, causing dreadful destruction, with whole cities lost. Usually this fear assumes that the Soviet leaders would expend the bulk of their missile force to destroy our cities. Yet if only a fraction of the attacking force were to reach some unpredictable targets, while missing most of the militarily important targets, to launch such an attack would accomplish no rational purpose. It would serve no strategic objective, and would be akin to a wanton terrorist act. It is precisely against such irrational acts that an exclusive reliance on deterrence would offer no protection at all.

We cannot know at this time whether the Soviet Union will join us and agree on major reductions in offensive nuclear arms, and whether it would abide by them. As one tries to promote arms control, Soviet failure to comply with past agreements is a bone in one’s throat. But if the Soviet leaders are willing to cooperate on a purpose both East and West can share, that purpose surely cannot be the perpetual hostility that is inherent in unopposed forces constantly poised for mass destruction. It can however be a strategic order that will eventually eliminate Soviet vulnerability to massive nuclear destruction, even if this means in turn surrendering their capability to inflict mass destruction on Western Europe and the United States. Conversely, should the Soviet leaders choose to preserve their doomsday capability at any price, the prospects for arms control would be bleak indeed.

The more the offensive armaments can be reduced by agreement, the easier and cheaper the job of providing effective defenses. Yet, to be realistic about Soviet motivations, we must seek to develop and deploy systems that can provide effective defenses even without such reductions. The United States is now pursuing new technologies that hold promise for success on the "hard road" as well. Thus, we make it all the more probable that the Soviet leaders will join us some day on the easy road of cooperation.

Our thinking on nuclear strategy must reach far into the future. It is not enough that our strategy serve to prevent nuclear attack in this decade or the next. Nuclear armaments and defensive systems take ten years or more to design, develop and build; and once deployed they will last for a quarter-century or more. We are today constrained in the choices for our nuclear policy by strategic theories that 30 years ago began to influence the development of our present weapons systems. The time to start designing a safer nuclear strategy for the twenty-first century is now.

For a few more years, to be sure, many arms control experts, military technicians and bureaucrats in our alliance will cling to the dogma of the allegedly stable consensual vulnerability. They will marshal all sorts of evidence to prove, as an "iron law," that the means for nuclear attack will always outpace the means for defense, keeping mass destruction an inescapable threat for all nations.

One is reminded of another theory that was influential at the beginning of the last century: Thomas Robert Malthus marshaled a huge body of evidence to prove that the growth of population will always outpace the means of subsistence, keeping mass poverty an inescapable condition of mankind. Malthus’ theory became so influential because it combined a seductive simplicity and rigor with an important kernel of truth (a truth to be seen this day in many impoverished regions of the world).

The Malthusian theory turned economics, as Thomas Carlyle put it, into "the dismal science." Yet today all economists, regardless of differing views on population policy, agree that new factors have negated Malthus’ iron law. The nineteenth-century marriage of capitalism and modern science brought forth such an immense creation of wealth—enhanced by the social and cultural benefits of modern democracy—that economics ceased to be a dismal science.

Nuclear strategy, too, will cease to impose its dismal prospect on the future, if we now apply our creativity in science, technology and statesmanship to build a new order for preventing nuclear war.

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  • Fred Charles Iklé has been the Under Secretary of Defense for Policy since 1981. He was Director of the U.S. Arms Control and Disarmament Agency in the Nixon and Ford Administrations, 1973-76.
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