Charles L. Glaser

Realists as optimists: Cooperation as self‐help

~ Structural realists are pessimistic about the prospects for international cooperation; they believe that competition between the major powers in the international system is the normal state of affairs. The structural-realist argument is driven by the implications of international anarchy, that is, the lack of an international authority capable of enforcing agreements. Responding to the pressures of anarchy, during peacetime countries will be inclined to deal with adversaries by arms racing and gaining allies, rather than by cooperating via arms control or other approaches for realizing common interests. Anarchy discourages cooperation because it requires states to worry about the relative gains of cooperation and the possibility that adversaries will cheat on agreements. In short, the standard structural-realist argument predicts that cooperation between adversaries, while not impossible, will be difficult to achieve and, as a result, will be rare and contribute relatively little to states’ well-being.’ This characterization of structural realism is offered by both its proponents and its detractors. Kenneth Waltz argues that self-help systems “make the cooperation of parties difficult. . . . Rules, institutions, and patterns of cooperation . . . are all limited in extent and modified from what they might otherwise be.” Summarizing the views of realists, Joseph Grieco says, ”realism presents a fundamentally pessimistic analysis of the prospects for international coop-

What Is the Offense-Defense Balance and Can We Measure It?

Offense-defense theory offers an optimistic view of international politics based on the argument that war can be prevented if defense gains an advantage over offense. It also argues that an effective arms control can reduce the risk of arms races and war. The theory has been useful in foreign policy analysis and in international relations scholarship since it is used to explain theoretical and policy issues and the causes of World War I and ethnic and civil wars and to predict post-Cold War Europe political relations.

Why NATO Is Still Best: Future Security Arrangements for Europe

T h e end of the Cold War and the dissolution of the Soviet Union have generated extensive interest in redesigning Europe’s security structures. Cold War dangers have dramatically receded, raising questions about the continuing necessity of the North Atlantic Treaty Organization (NATO). New dangers in Central Europe, already too apparent in the former Yugoslavia, have fueled doubts about the ability of Europe’s institutions, including the Conference on Security and Cooperation in Europe (CSCE), the European Community (EC), the EC‘s defense component-the Western European Union (WEU)-as well as NATO, to manage the dangers of post-Soviet Europe. Although discussion of various institutional arrangements is already extensive, little systematic analysis of their relative strengths and weaknesses is available. This article attempts to fill the gap: it first explores U.S. and Western European interests and potential threats to these interests; it then assesses the ability of specific proposed security arrangements to confront these threats. The first section distinguishes three types of current or future war the West might face. The first danger is of deliberate attack from a major power in the East-a resurgent Russia. The second is war in the East, including wars that begin in Central Europe but could draw in the West. The third is war within Western Europe, possibly exacerbated by war in the East. The dangers that these wars pose to the West depend on their probability and on the Western interests they would threaten. Based on the current state of debate, my assessments are that the probability of a resurgent Russia is small but is not necessarily decreasing; that the probability of more wars in

Structural Realism in a more complex world

The editors of the Review of International Studies have posed a timely challenge to what they term American realism. In broad terms, their editorial makes two points: first, realism has lost its relevance to current international policy; and second, realism does a poor job of explaining the behaviour of the worlds major powers. In this brief essay I argue that both of these points are greatly overstated, if not simply wrong. At the same time, I accept that realism provides less leverage in addressing the full spectrum of issues facing the major powers in the post-Soviet and now the post-9/11 world than it did during the Cold War. However, this is neither surprising nor a serious problem, because scholars who use a realist lens to understand international politics can, and have, without inconsistency or contradiction also employed other theories to understand issues that fall outside realisms central focus.

Counterforce Revisited: Assessing the Nuclear Posture Review's New Missions

Current U.S. nuclear strategy identifies new nuclear counterforce missions as a means of impeding the proliferation of weapons of mass destruction. The strategy appears to overvalue these counterforce missions. U.S. conventional weapons can destroy most targets that can be destroyed with nuclear weapons; only moderately deep and precisely located targets can be destroyed only by nuclear weapons. In addition, the benefits of nuclear counterforce-which could include deterrence, damage limitation, and the continued ability of the United States to pursue its foreign policy objectives-are relatively small, because the United States possesses large nuclear forces and highly effective conventional forces. Finally, nuclear counterforce would bring a variety of costs, including an increased probability of accidental war and unnecessary preemptive attacks in a severe crisis. Nevertheless, the case for nuclear counterforce is stronger than during the Cold War, when the enormous size and redundancy of U.S. and Soviet forces rendered counterforce useless. When facing a small nuclear force, the United States may decide to use counterforce to limit damage. Although complex trade-offs are involved, if there are critical targets that can be destroyed only with nuclear weapons, then under a narrow set of conditions the benefits of planning for damage limitation might exceed the dangers. The United States must not, however, rely on nuclear counterforce to support a more assertive foreign policy; doing so would unjustifiably increase the probability of nuclear war.

Correspondence: Taking Offense at Offense-Defense Theory

I n his article ”Offense, Defense, and the Causes of War,”’ Stephen Van Evera claims that ”offense-defense theory” is ”important,” has “wide explanatory range. . . . wide realworld applicability. . . . large prescriptive utility. . . . [and] is quite satisfying” (p. 41). Van Evera’s conclusions are, however, unwarranted. First, his reformulation of influential arguments made prominent by Robert Jervis stretches the meaning of key concepts such that interesting avenues of empirical inquiry are closed off rather than opened. Second, the hypotheses--or “prime predictions”-Van Evera derives from the theory are themselves products of faulty deductive logic. Furthermore, they are nontestable, presumably nonscientific in Van Evera’s understanding of the term.’ Van Evera’s results are thus of little use to the social scientist who is interested in understanding the myriad causes of war and conditions facilitative of peace. In his classic article, “Cooperation under the Security Dilemma,” Jervis argued that the security dilemma is more virulent and the international system less stable when offense enjoys an advantage over defense. By contrast, when defense is more potent, status quo powers find it easier to adopt compatible security policies, and the pernicious effects of international anarchy are greatly d imin i~hed .~ Although the operation-

The flawed case for nuclear disarmament

Proponents of nuclear disarmament argue that it will decrease the probability of deliberate nuclear war, is necessary to eliminate the possibility of accidental nuclear war, and will contribute to the prevention of nuclear proliferation. The first argument is wrong - disarmament is more likely to increase the probability of deliberate nuclear war. The second argument exaggerates the benefits measures far short of disarmament can greatly reduce the dangers of accidental use. The third argument is correct, but for reasons overlooked by proponents - disarmament would make nuclear proliferation so threatening that the major powers would become willing to launch large preventive conventional wars. Although disarmament would bring some benefits, for the foreseeable future the major powers will be more secure in a nuclear world.

ICBM Vulnerability: The Cures Are Worse Than the Disease

I T h e Soviet Union has the means to destroy the United States. An attack by only a fraction of the thousands of nuclear warheads now deployed on Soviet long-range missiles and bombers would be sufficient to annihilate most Americans, to destroy our material accomplishments, and to transform our country into a wasteland. We have virtually no defense against such an attack. Our nation is vulnerable, and has been for decades. The Soviets could also destroy a substantial portion of our military might. Land armies, surface ships, airfields, theater-based nuclear forces, and command, control, and communications facilities are especially vulnerable. Of the strategic forces, those at greatest risk are the ballistic missile submarines in port (normally about half of the SSBN force) and those long-range bombers not on alert (normally about two-thirds of the bomber force). These vulnerabilities too have been recognized for decades. The comparative newcomer to the world of vulnerability concerns is the land-based ICBM force, for it is only recently that the numbers, yields, and accuracies of Soviet ICBM warheads have approached the levels required to pose a meaningful threat to a large number of hardened silos. Opinions differ on whether this threat is credible in light of the substantial uncertainties inherent in predictions of the outcome of such a complex, sophisticated, unprecedented, and untestable attack. But in theory at least, a large fraction (perhaps as high as ninety percent) of America’s ICBM silos could be at risk within the next few years. Heightened awareness of this potential vulnerability has been an important factor in the perception of declining American strategic power, in the rhetorical opening of the “window of vulnerability,” and in the demise of SALT 11. Why, it might be asked, should one worry about ICBM vulnerability? Why should this particular instance of vulnerability deserve our attention any more than the other vulnerabilities cited previously? Some observers believe that a survivable land-based ICBM force is essential to U.S. security; others find the need less than compelling, but still substantial; and still others

When Are Arms Races Dangerous? Rational versus Suboptimal Arming

Are arms races dangerous? This basic international relations question has received extensive attention.1 A large quantitative empirical literature addresses the consequences of arms races by focusing on whether they correlate with war, but remains divided on the answer.2 The theoretical literature falls into opposing camps: (1) arms races are driven by the security dilemma, are explained by the rational spiral model, and decrease security, or (2) arms races are driven by revisionist adversaries, explained by the deterrence model, and increase security.3 These When Are Arms Races Dangerous?

Should the United States Reject MAD? Damage Limitation and U.S. Nuclear Strategy toward China

As China invests in its nuclear forces and U.S.-China relations become increasingly strained, questions of U.S. nuclear doctrine require greater attention. The key strategic nuclear question facing the United States is whether to attempt to maintain and enhance its damage-limitation capability against China. The answer is less straightforward than it was during the Cold War, because Chinas nuclear force is orders of magnitude smaller than the Soviet force was. Part of the answer depends on the military-technical feasibility of the United States achieving a significant damage-limitation capability: What would be the outcome of military competition over the survivability of Chinas intercontinental ballistic missiles, submarine-launched ballistic missiles, and command and control, and over the effectiveness of U.S. ballistic missile defenses? The answer also depends on the benefits that a damage-limitation capability would provide; these could include contributions to homeland deterrence, extended deterrence, and reassurance of U.S. regional allies. The final piece of the analysis concerns the potential costs of a damage-limitation capability, which could include increased escalatory pressures during crises and growing political tension between the United States and China. A thorough analysis demonstrates that the United States should forgo such a capability because the prospects for preserving a significant damage-limitation capability are poor; the deterrent benefits would be small; and the escalatory and political costs would be relatively large.