Nuclear Weapons and Intergenerational Exploitation

Nuclear weapons' defenders claim that they lower the risk of war, at the price of devastation if war breaks out. Sooner or later, however, on a realist analysis, catastrophic nuclear war is sure to come. Nuclear deterrence thus buys us a better chance of dying in bed, while each post-holocaust generation will have to pick up the pieces. If the nuclear optimists are wrong, hoping to spread or perpetuate nuclear deterrence is foolish; but if they are right, it is exploitative. Like big cars and cheap flights, nuclear deterrence benefits us at the expense of future generations. States that do not already have the bomb should not get it. Britain and France should consider disarmament, while Russia and the United States should slash their arsenals. Minimum deterrence should be equally stable, but most nuclear optimists, being neorealists who hold that war will continue, should want deep cuts even if it is not.

Nuclear Weapons and Intergenerational Exploitation 527 fact, we can no more assume a harmony of interests among generations than among nations. Just as the belief that all states benefit from the international status quo muddles analysis, 9 so too does the assumption that all generations gain or lose from nuclear deterrence. To say, for example, that nuclear disarmament could "reduce U.S. security" by making conventional war more likely 10 is misleading because it fails to specify which Americans. Compared with the status quo, disarmament might well reduce present people's security, while benefiting those born three hundred years from now. Similarly, if Ukraine had retained its nuclear weapons, as John Mearsheimer urged, this might have discouraged Russian attack. 11 If he is right, however, that war is endemic to international politics, it would surely have meant losing Kiev later. Seen like that, nuclear deterrence seems a less savory bargain. Unlike Faust, who took his sins on his own head, we are sending our descendants to hell.
This article builds a bridge between recent nuclear debates and philosophical writings on intergenerational justice. 12 Most critics of nuclear deterrence and proliferation have argued that either that it is intrinsically wrong to target civilians or war is more likely than we think. Here I assume that enemy civilians are fair game and show that nuclear deterrence leads to morally rotten consequences if the nuclear optimists are right. First, I summarize the logic of optimism and argue that, even if these weapons reduce the risk of conflict, under realist assumptions catastrophic war remains inevitable. Next, I outline three theories of intergenerational justice-based in social contract theory, distributive justice, and utilitarianism-and show that in each case nuclear deterrence fails the test. As when we drive SUVS or run up budget deficits, here too we scoop the benefits while passing on the costs. It is a wicked bargain, but does much to explain why both fossil fuels and the bomb are so hard to give up. 9 Edward Hallett Carr, The Twenty Years ' Crisis, 1919' Crisis, -1939 10

M. Rendall
Third, I contend that states that have not yet obtained nuclear weapons have no justification for doing so-even if, in the short term, it would make them more secure. Sooner or later war will come and instead of Baghdad or Tehran they will inherit rocks and radioactive ash. Advocates of horizontal proliferation, like Mearsheimer and Kenneth Waltz, are unwittingly inviting people to exploit their own descendants. Nevertheless, it is Russia and the United States with their huge arsenals, not "rogue states," that pose the greatest threat to the planet. Ideally, they ought to abandon all their nuclear weapons, but nuclear states cannot reliably bind themselves not to rearm in the course of a conflict. A failed attempt at disarmament could make catastrophic war more likely rather than less. The best Moscow and Washington can do under present conditions is to slash their arsenals.
The logic of nuclear optimism implies that minimum deterrence at around 200 warheads each should be at least as stable as the status quo. Neorealists should support deep cuts in Russian and American forces even if it is not. They believe major war cannot be banished from world politics. Given a choice between war sooner with limited damage and war later with unlimited damage, we ought to prefer the former since we internalize more of the costs of our own defense. Liberals, Marxists, and constructivists may contend that nuclear war is not inevitable and a failed attempt at minimum deterrence could stymie trends toward international peace, but if Moscow and Washington should seek to justify huge arsenals on this ground, they ought to be working much harder to promote a peaceful world.
This article strips away the fig leaf in which optimists have clothed the bomb. If nuclear weapons do not make war less likely, seeking to spread or perpetuate them is foolish. If they do, it is exploitative. States that face a severe threat will go nuclear regardless of the long-term consequences. Nevertheless, my argument has practical implications. Not all states confront dire existential threats. Sometimes whether they acquire the bomb will depend on fierce internal battles in which ethical considerations may tip the balance. For outsiders to encourage proliferation in such cases is not just a blunder, but a crime. Moreover, the logic of nuclear optimism suggests nuclear states can and should go down to minimum deterrents. Nevertheless, critics of the status quo face the same challenge as other environmental activists of convincing people to change policies from which they reap most of the benefits and pass on most of the costs.

A FAUSTIAN BARGAIN-BUT WHO PAYS THE BILL?
Nuclear weapons, so goes the case for the defense, make aggression hard and deterrence easy. States can hope for only small gains if they go to war. We may chip away at an adversary's border, but if we march on its capital, we risk our own annihilation. Even gamblers grow cautious when faced with the bomb. Whereas states may start a conventional war without being sure they can win, any state that provokes nuclear retaliation against its cities can be certain it will lose. We need not even know that the opponent will strike back; we need only fear it might. Nuclear weapons make calculating the costs and benefits of war easy. "Do we expect to lose one city or two? Two cities or ten?" asks Kenneth Waltz. "When these are the pertinent questions, political leaders stop thinking about running risks and start worrying about how to avoid them." 13 The bomb cuts the chance of war because it is so destructive.
Nuclear weapons have several other helpful effects. First, strategies based on mutual assured destruction (MAD) mitigate the security dilemma. With MAD we do not need more nuclear weapons than the opponent or even as many; we need only enough to inflict unacceptable damage. Sensible leaders see they need not run arms races; indeed, they can tolerate huge changes in relative power. Territorial expansion is not necessary, nor does it add much security. States can pursue conventional arms control with less anxiety. In a crisis they have little incentive to strike first, since even after losing much of their force they can inflict intolerable damage on the opponent. Second, since most states covet their neighbors' territory less than they value their own, coercive threats are less credible than threats of retaliation. Deterrence thus favors defenders and reinforces the status quo. Finally, states do not have to mobilize public support for conventional armies. Because the bomb is an absolute weapon, they no longer need to keep up with the Joneses (or Ivanovs), and in any case nuclear weapons cost less than soldiers. This spares leaders the task of whipping up support for high military spending and makes nuclear states less prone to hypernationalism. 14 On such grounds, some optimists advocate limited proliferation. 15 530

M. Rendall
Barring Radical Change, Catastrophic War is Just a Matter of Time Most critics of the nuclear peace thesis have sought to show that war is more likely than the optimists claim. Even if nuclear deterrence makes war very unlikely, it is a good bargain only if the risk of nuclear war is so low that it is worth running to prevent another World War I or II. 16 Since the first time deterrence failed could be the last, this is a high hurdle for it to clear. 17 At times Waltz seems to have trouble seeing how war could break out at all. Nevertheless, even he admits that nuclear deterrence can fail. 18 Fierce leaders may be willing to pay high costs. While only a fanatic would choose a nuclear war, we know from the Cold War that others will risk it. Since nuclear brinksmanship inevitably entails a danger that things may get out of control, states in a crisis can stumble into war. 19 Indeed, evidence from the Cold War shows that we were lucky not to blunder into it. 20 How low is the risk of major war among nuclear states? Waltz claims that it "approaches zero." 21 Here, "approaches" is not good enough. As long as the risk of nuclear war does not steadily decrease, if we wait long enough it becomes a near certainty. 22 Some events-such as monkeys typing Hamlet by striking keys at random-are so unlikely that we can effectively treat them as impossible. Even over eons, the chances are tiny that they will ever occur. 23 Nuclear war does not fall into this category. In the six decades since the atomic bomb was invented, we have already seen one nuclear war (though a small and one-sided one), a superpower crisis in which President Kennedy estimated the risk of war at between one in three and one in two, 24 and several other scares and confrontations in which the risk of war was small but not negligible. While we can only guess at the statistical probability, an estimate of one percent per year during the Cold War does not seem outlandish. By 1989 it was probably less, 25 while at points, such as the Berlin and Cuban crises, it was surely higher. At a rate of one percent, the risk exceeds fifty percent after sixty-nine years. 26 Today, the risk that the United States or Russia will deliberately start a nuclear war has fallen, but with the erosion of Russian command and control, the risk of accidental war may actually have risen. "Given the exceedingly short reaction time that is available to decision-makers," T.V. Paul observes, "there is all the more reason to worry about a 1914 scenario of misjudgments, miscalculations and strategic fatalism occurring in the future . . . ." 27 Moreover, we may be in the lull between storms. Nuclear rivalries and arms races are likely to resume. Under multipolarity, the risk could be greater than before. 28 Washington and Beijing may manage their rivalry as successfully as did Washington and Moscow, but we should not bank on it. Most important of all, the greater the number of nuclear states, the bigger the risk that one will start war by accident or fall under the control of a madman. 29 Even if new nuclear states handle their weapons no worse than the superpowers did, can we assume they will do better? 30 At several points during the Cuban missile crisis, things could have gone badly wrong. 31 Poor states have strong incentives not to build as many weapons as the Soviet Union and the United States built, 32 but this may not be true for China, India, or other rising powers. When those states have their Cuban crises, will they be as lucky as their predecessors? Sooner or later the cards will fall against us, and with enough time, in a big way.
Waltz mocks such calculations, pointing out that in 1960 C. P. Snow claimed it was a "statistical fact" that nuclear weapons would be used in the next ten years. "Apparently," Waltz scoffs, "fifty-some years is not a long enough run to confirm the stability of nuclear deterrence." 33 Indeed, it is not. A few decades of uneasy peace are far too short a time to show the probability of nuclear war at all. Was the risk over the last half century forty percent, or 27  was it merely fifteen? We have no way to tell. 34 Even if nuclear deterrence is like Russian roulette, Joseph Nye argues, there is a great difference between games when the pistol has six chambers and when it has a hundred. 35 That is true-if one plays only a few times. Nuclear deterrence, however, is Russian roulette played every day for decades. Even if relations among the nuclear powers are good, on any day of the year there is some chance of nuclear war, as Russia's 1995 activation of its "nuclear suitcases" showed. 36 The risk of being "shot" need not rise over time. Still, one cannot play Russian roulette indefinitely. Seen from the perspective of a human lifespan, whether a pistol goes off within a few days or a few weeks makes little difference. Similarly, whether large-scale nuclear war comes next year or in two centuries matters little over the long haul of the earth's history, though it makes a difference to us.
Barring revolutionary changes in technology or the states system, if we keep nuclear weapons for hundreds or thousands of years, they are going to be used-by accident or design. We may have colonized nearby planets by then, or other changes may have made nuclear weapons irrelevant. 37 Or they may not. Arguing in favor of missile defense, William Safire claims that "hitting a bullet with a bullet is hard to do," but "in time, after costly trial and error, the new defense will surely leapfrog the old offense, as it always does." 38 Always? In the five hundred years since small arms appeared, nobody has discovered how to shoot down a bullet. Why assume that missile defenseor any other technical solution-will be more successful? Some innovations are not easily neutralized, and nuclear weapons may be one of them. Richard Garwin has noted that if we start with an annual risk of nuclear war of one percent and can reduce it by 20 percent each year, the total risk for all time will amount to under five percent. This leads Nye to conclude that "if we can continually reduce probabilities [of nuclear war], failure is not inevitable in any meaningful time frame." 39 Aspiring to reduce the risk of nuclear war by twenty percent every year is optimistic even for a liberal. For realists, while the risk of war may vary, there is no reason to think it will steadily decline at all. 40 Nuclear weapons would have posed a serious threat to humanity any time in the past three thousand years.
Given that realists believe that conflict is a fact of life and are skeptical of quick fixes to enduring international problems, it is odd that many are so 34  sanguine about nuclear weapons. 41 Keith Payne, for example, attacks abolitionists for combining pessimism about the prospects for war with faith that disarmament is possible. 42 He has a point, but the argument can be turned around: Why think that disarmament will fail, but that deterrence is likely to succeed indefinitely? 43 Surely realists should conclude that both pessimistic views are justified. Is anything more utopian (or despairing) than a British official's remark that "we've got to try and make stable deterrence work for the rest of history"? 44 "Simple statistical probability," Campbell Craig observes, shows that the continuation of anarchy and of nuclear deterrence will sooner or later result in war, thermonuclear war. In the long term deterrence is bound to fail: to predict that it will succeed forever, never once collapsing into a nuclear war, is to engage in a utopian and ahistorical kind of thinking totally contrary to traditional Realist philosophy, as well as to defy the irrefutable logic of infinite probability. 45 There are good realist reasons to think we may be stuck with nuclear weapons whether we like it or not, but we should not like it. Realism is a tragic philosophy, not a Panglossian one. Handed lemons, realists should not make lemonade. The outlook is certainly bleak. Human casualties from an all-out nuclear war between NATO and Russia could be in the hundreds of millions or billions. At worst, the smoke from burning cities and oil facilities could plunge the earth into chilly darkness, though some claim that predictions of "nuclear winter" are overblown. The environment would remain poisoned for thousands of years. 46 Waltz argues that if nuclear war breaks out, no state is likely to escalate it to apocalyptic levels and if weak states acquire and use nuclear weapons, "the world will not end." 47 He is probably right about the first nuclear war, but unless a nuclear exchange revolutionizes world politics, states will remain in competition. A small nuclear war might provide the swift kick needed to get states to accept world government or other radical reforms, 48 but this seems unlikely. Even if it did not teach states that nuclear weapons were usable, 49 the brutality and resulting bitterness would more likely make their relations Hobbesian. What country would join a federation with a state that had just destroyed two of its cities? Eventually-in the second, third, or twenty-eighth nuclear war-fanatics, fools, or leaders fearing preemption will be at the helm and use large numbers of hydrogen bombs.

No Harmony of Interests
"It is true that nuclear weapons, very attractive as a deterrent, begin to look awfully unattractive when the focus shifts to war fighting," says Mearsheimer. ". . . This is a Faustian bargain, attractive only because the alternative-a reasonable chance of destructive great power conventional war-seems worse." 50 Worse for whom? Who gains from this bargain, and who loses? If the optimists are right, nuclear weapons give the inhabitants of nuclear states a better chance of dying in bed. True, when major thermonuclear war breaks out, many or most will be killed, but that is unlikely to happen in our lifetimes or even in our grandchildren's. These benefits are not evenly shared out. Non-aligned states face the side effects of nuclear war-which could be huge 51 -without the gains. 52 Wild animals, who are more likely to suffer from nuclear than conventional war, also get the short end of the stick.
Notably, nuclear deterrence discriminates among generations. Nuclear deterrence, however stabilizing, is not foolproof. Stephen Van Evera argues that proliferation would be "a net benefit to peace in Europe," 53 but acknowledges that MAD "becomes a nightmare if nondeterrable nuclear actors appear." A nuclear world with the likes of Adolf Hitler would be still more dangerous than a conventional one. He takes comfort in the thought that "this danger is not at the world's doorstep." 54 But sooner or later, unless the world has been transformed, new Hitlers will appear. Proliferation might be a net benefit over the next fifty years, but not the next five hundred. Nuclear optimists falsely assume an intergenerational harmony of interests. If they are right, we all gain from deterrence until it breaks down. But it will break down. To 48 Booth and Wheeler, "Beyond Nuclearism," 41; Nye, Nuclear Ethics, 62-63. 49  stop worrying and love the bomb means to doom our descendants, to save our own miserable hides.

INTERGENERATIONAL EXPLOITATION
Nuclear deterrence thus raises issues of intergenerational justice. Intergenerational justice deals with our obligations to past or future generations, particularly those with which our own lives do not overlap. 55 Certain actions-such as cutting down forests or producing radioactive waste-let us make gains at our descendants' expense. Tax cuts now and debt repayment later can be a winning formula for re-election, as recent U.S. history shows. "In many intergenerational situations . . . it is less costly in the short term to ignore the problem," observes Kimberly Wade-Benzoni. ". . . In the long run, however, it ends up costing more-but those costs accrue to a different set of people." 56 Intergenerational exploitation is particularly common in the environmental sphere. Nuclear power raises many of the same distributive issues as nuclear deterrence. We enjoy the electricity now; future generations face most of the risks. We exploit our descendants by creating an externality in our favor, since "future generations must bear very significant costs without having received the benefits of the activities prior to the accident" 57 -so too with nuclear deterrence. The objection that "no reasonable person with even a limited acquaintance with the history of human affairs over the last 3,000 years could be confident of safe storage by methods involving human intervention over the enormous time periods involved" 58 applies at least as much to nuclear weapons as to nuclear waste. Does any reasonable person, let alone a realist, expect deterrence to work for millennia without catastrophic "accidents"?
Many of us feel intuitively that to squander resources or hand down heaps of radioactive waste to future generations is wrong. 59

Social Contract Theory
John Rawls argued that those institutions are just which rational egoists would choose if they were ignorant of the position in society they would occupy. If such egoists were to choose a rule which they wished all previous generations had followed, it would be in their interest to avoid intergenerational exploitation. 61 If we did not know whether we would be born in 1960, 2400, or 3700, surely we would not agree to our present squandering of fossil fuels that is heating up the planet. The risk of being born into a later generation would be too great. Nor would we agree to rely on thousands of nuclear weapons that may leave, by 3700, little planet to inherit. This is all the more true because the benefits of nuclear deterrence may last for only a century or two before it breaks down, while a nuclear war's survivors will have to deal with the consequences for thousands of years. Even if we assume that the earth's population would be much smaller after a war, the odds of being born into a post-holocaust generation would be high indeed.

Distributive Justice
We can also appeal to the principle of distributive justice. Future generations deserve opportunities as good as we have had, and this includes a livable planet. 62 It also means the right to inherit what past generations have built up. It is true that past people were under no obligation to write Crime and Punishment or build the Library of Congress, and in that sense we have no 60 Some critics may invoke what Derek Parfit calls the non-identity problem. See Derek Parfit, Reasons and Persons, chap. 16. Nearly any major public policy affects who is born and who is not. If we rely on nuclear weapons, different people will be born than if we had relied on conventional deterrence instead. Hence, even if this leads to disaster, so long as postwar people find their lives even minimally worth living, we will not be able to identify specific individuals whom nuclear weapons have harmed. Philosophers have suggested a variety of responses to the non-identity problem. Perhaps the best response is that it violates our basic moral intuitions. It means, for example, that squandering resources harms no one in the far future, since different people will be born than if we conserve. Such claims, as Parfit himself says, are scarcely plausible. Ibid., 378. In any case, for the non-identity problem to apply, future people must find life worth living. If their lives are wretched-as could well be the case after nuclear war-they could blame us for creating the conditions for them to be born at all. right to inherit them. 63 Since they did create those goods, however, future generations have the same right to enjoy them as we did. In one sense, I do not deserve to inherit a family fortune that I have not lifted a finger to earn. Still, if my father hocks the family heirlooms and squanders the money on champagne and caviar, he wrongs me as well as our ancestors. 64 Likewise, we hold the planet in trust for future generations as well as our own. 65 Critics will object that mere existence is not the only thing worth handing down. Nuclear deterrence may protect other parts of the human heritage, such as free political institutions. "If we have benefited from 'life, liberty, and the pursuit of happiness,"' Nye asks, "why should we assume that the next generation would want only life?" After all, we take a risk every time we get into a car. 66 This confuses threats to individuals with threats to the environment. If I expect to live another fifty years, risking a car accident is a reasonable cost-benefit calculation. If the greenhouse effect threatens the future of life on earth, the calculus of driving becomes very differentso too with nuclear weapons. However desirable it may be to preserve the better aspects of our civilization for future generations, this pales against the obligation to preserve the natural world and favorable conditions for life on it, because they can last for so much longer. "If we do not soon destroy ourselves, but instead survive for a typical lifetime of a successful species," note Carl Sagan and Richard Turco, "there will be humans for another 10 million years or so. Assuming that our lifespan and numbers do not much grow over that period, the cumulative human population-all of us who have ever lived-would then reach the startling total of about a quadrillion (a 1 followed by 15 zeros)." 67 Moreover, this is just one species. Vertebrate animals have been around for some half a billion years; human beings for 63  Pasek, Justice, Posterity and the Environment). Yet a terrorist who sets a time bomb that kills a dozen children eighty years later violates their rights even though the children were not born when the bomb was set and the bomb-maker is no longer alive when it goes off. Even an unborn child, as Joel Feinberg points out, can have the right to property, "contingent upon his birth, and instantly voidable if he dies before birth . . . . Assuming that the child will be born, the law seems to say, various interests that he will come to have after birth must be protected from damage that they can incur even before birth." That temporal logic precludes a future person from demanding his or her rights, whereas babies are merely physically and intellectually incapable of doing so, seems a morally irrelevant distinction. Barring catastrophe, sentient life, even human beings, will outlast Locke and Jefferson by a tidy few millennia. Past generations have thought their ideals worth preserving, but we would not want them to have put the planet at risk to do so. Suppose that nuclear weapons had been discovered in the twelfth century. Would the Crusaders have had the right to risk nuclear holocaust to save Christian Jerusalem from the Saracens? Would we countenance nuclear brinksmanship by Philip II in the name of the Counterreformation? As Barrie Paskins says, "Who are we, beings with a life expectancy of decades, to discuss the entire future of the planet in terms deriving exclusively from our concerns, concerns which may be expected to count for nothing in a few millennia with or without nuclear war?" 68 Some will claim that this argument allows the future to tyrannize over the present. 69 Theories of distributive justice, however, may establish limits on what we owe. 70 We need not live in slums so that our grandchildren can live in palaces, because this would mean extreme and avoidable inequality. Nuclear deterrence, conversely, is in the long run almost sure to leave many future people worse off than we are. Any progress the future brings will be cancelled out by a major thermonuclear war-to say nothing of the calculus for non-human animals. Nuclear deterrence thus violates the principle that we should "leave 'as much and as good' of the public goods previous generations have bequeathed" 71 -such as a nonradioactive landscape-as we have enjoyed ourselves.

Utilitarianism
Nuclear deterrence is also incompatible with total utilitarianism, which says we should want the greatest good for the greatest number. 72 Whatever benefits we presently draw from deterrence will be outweighed by centuries or millennia of suffering after it breaks down. Average utilitarianism, in contrast, says we should maximize the welfare of however many beings exist. If war killed everybody, average utility might remain fairly high. We would enjoy the blessings of deterrence until war broke out, and after that we would all be dead. Research in the 1990s, however, indicated that even catastrophic war 68  should not kill everyone, 73 and as long as some people or sentient animals survive a holocaust, nuclear deterrence will also reduce average utility. In any case, if nuclear war should drive us to extinction, this is hardly a moral argument in its favor.
If only a single generation-call it generation H-stood to suffer from nuclear war, we might defend deterrence on contractarian or utilitarian grounds. Each generation, contractarians might claim, makes the Faustian bargain, and if war comes along on its watch, tough luck. Utilitarians might hope the benefits that preceding generations A through G enjoyed from the nuclear peace would outweigh the suffering of generation H. A nuclear war, however, would penalize not only the generation that drew the short straw, but all generations that lived after it. We take a small risk of a nuclear conflict and enjoy a low risk of conventional war. Wartime generation H enjoys the benefits of nuclear deterrence until it breaks down, but its descendants are left picking up the pieces. Here, if the optimists are right, is where the exploitation comes in. Should the first few wars remain limited, their survivors may continue to benefit from the lower incidence of war nuclear weapons provide. As wars recur, the costs of deterrence will mount compared to its benefits, and those benefits will be wiped out almost completely when at last the "big one" arrives.

Cosmopolitan Versus Nationalist Ethics
The foregoing analysis has been cast in terms of what is right for the world. Many realists argue in just this way. Urging states to pursue their selfish interests, they often justify doing so through cosmopolitan arguments. 74 Waltz, for example, defends horizontal proliferation in terms of its effects on the system. Yet some may say that a state's primary duty is not to the world, but to its own citizens. 75 This rests on the observation that government involves a fiduciary relationship. 76 Leaders, one might argue, have no more right to endanger their country's interests than trustees have to donate the money entrusted to them to UNICEF. Even if one accepts this view of trusteeship, 77 it does not follow that they should protect their citizens at other countries' expense. Though trustees bear an obligation to protect their charge's interests, this does not mean they can do anything they please to innocent bystanders. While it may be wrong to give Tommy's trust fund to charity, it would also be wrong to enlarge the fund by embezzling money from Tina's. Similarly, it may be wrong for states to increase their security through nuclear deterrence at the expense of neutral third parties.
Let us suppose, however, that leaders do have the right to harm other countries in the interest of their own citizens. Do nuclear weapons help them to do this? A state might increase its citizens' security by acquiring a nuclear monopoly, but such a monopoly is unlikely to last. Historically, one state's acquisition has often led its rivals to follow suit. 78 What if a state's rival is going nuclear? Here leaders have often believed that the best way to protect national security is to nuclearize in response. This may be true in the short term, but in most cases conventional defense or even surrender would be a better way to ensure long-term national security. An enemy is most unlikely to launch a full-scale nuclear attack against a non-nuclear state, though it might use a few weapons for coercion. If only State A has nuclear weapons, it has little incentive to preempt in a crisis, and State B cannot preempt. 79 Nor is a limited nuclear war as likely to get out of control because there is no risk of reciprocal escalation. While nuclear deterrence may save the next few generations from being Red, it increases distant generations' chances of being dead, and that is not in the long-term national interest. 80 Even ethical theories that privilege national interests are very unlikely to demand nuclear deterrence, once future generations are factored in.
Confronted with a foreign adversary, states ought, in principle, either to rely on conventional defense or to surrender. If nuclear weapons are readily 78 Bradley A. Thayer, "The Causes of Nuclear Proliferation and the Utility of the Nuclear Nonproliferation Regime," Security Studies 4, no. 3 (Spring 1995): 486-93. 79 This assumes that State B's conventional weapons cannot threaten its nuclear force. 80 McMahan, "Nuclear Deterrence and Future Generations." One might argue that people in the far future will not belong to the same nation, and that states therefore owe a greater obligation to the next few generations. Reasoning along communitarian lines, Avner de-Shalit holds that our positive obligations to future people diminish as they become more distant. Nevertheless, he holds that "to people of the very remote future we have a strong 'negative' obligation-namely, to avoid causing them enormous harm or bringing them death, and to try and relieve any potential and foreseeable distress." De-Shalit, Why Posterity Matters, 13, 54, 63-65, quotation from 13. Nuclear deterrence flunks this test. The exception might be if a state's enemies are bent on genocide. Suppose Israelis fear that in the absence of nuclear weapons their enemies would murder the Israeli nation. If they are right, then nuclear deterrence could serve the interests even of future generations of Israelis. Despite the near-inevitability of eventual nuclear war, Israelis might consider this a lesser risk than that of Arab genocide. Before acting on such a conclusion, Israel should explore every conceivable alternative, including a conventional military build-up, appeasing the Arabs or even shutting down the Zionist enterprise and moving to other parts of the world. If none of these is a feasible means of securing Israelis' physical survival, then building a small nuclear arsenal might be justified. available, however, the latter is too much to ask. As David Lewis observes, even if surrender is the best of all choices, if a leader is not confident he or she could choose it, it may be unwise to try. Pakistan ought to give up its nuclear weapons in the interest of future generations, and in a war with India it should accept defeat rather than rebuild them, but surely it would not-and if Pakistan scrambled to rearm during a crisis, that might make nuclear war more likely. If this is so, as wrong as it is to rely on nuclear deterrence, this is a case where, in Lewis's words, "it is best to intend the second best." 81 As we shall see, second-best is minimum deterrence.

WHAT IS TO BE DONE?
Nuclear deterrence, if the optimists are right, buys today's inhabitants of nuclear states a better chance of reaching a ripe old age. It buys future generations rubble. If the optimists are wrong, the bargain looks still worse. Even if apocalyptic war is not inevitable, we should do all we can to avert it. "Where there is any risk of something infinitely awful happening," Robert Goodin remarks, "then probabilities simply do not matter. Just so long as that outcome is possible . . . we must do whatever we can to avoid it. Infinite costs, discounted by any probability larger than zero, are still infinite." 82 Certainly, if catastrophic war is even likely, the Faustian bargain is a bad one indeed. Barring major technological or political changes, however, in the long-run total war is inevitable-if not the first nuclear war, then the tenth or twentieth. Jacques Chirac asserts that "our [nuclear] deterrent guarantees . . . that France's survival will never be placed into question by a major military power." 83 Never? There is no security from long-term thermonuclear catastrophe.
In this devil's bargain, the archfiends are Russia and the United States, though other states may have forces big enough to threaten global disaster. 84 "States with large arsenals and faulty bureaucratic routines may accidentally fire warheads in large numbers," Waltz concedes, before adding, "States with small arsenals cannot do so . . . . Efforts should concentrate more on making large arsenals safe and less on keeping weak states from obtaining the small number of warheads they may understandably believe they need for security." 85 Waltz is right, but while only the great powers hold humanity hostage, China, India, and Pakistan are still buying security at their own descendants' expense. "We ought to be disturbed by the apparently permanent position of nuclear weapons in the international system, even acknowledging 81 Lewis, "Finite Counterforce," 74. 82 Goodin, "Nuclear Disarmament as a Moral Certainty," 274. 83  that there is now little that can be done about it," Lawrence Freedman wrote in 1989. "To believe that this can go on indefinitely without major disaster requires an optimism unjustified by any historical or political perspective." 86 Is there anything we can do about it? Mutual assured destruction may buy us security, but by mortgaging the future of untold future generations. We ought to prefer any policy that reduces the long-run threat to the world, even if it makes war more likely in the here and now. In principle, this can be done in two ways: by renouncing nuclear deterrence altogether or by developing a form that externalizes fewer costs to future people, even if we internalize more ourselves. The first is morally preferable to the second, but is open-at least for the most part-only to non-nuclear states.

Non-Nuclear States Should Renounce the Bomb
States that have not already developed the bomb should not do so. Indeed, given the threat that it poses to future people, they should not do it even if this makes them more likely to be blackmailed or conquered. 87 People five hundred years from now will not much care who ran the country in the twenty-first century or whether it retained a particular province, whereas if they have to live in ruined and radioactive cities, they may care very much indeed. States need not become pacifists, but they should restrict their defense to conventional means. North Korea mounted a strong deterrent even before it had nuclear weapons. Rather than threaten the Middle East with a nuclear arms race, Iran could follow Libya's example and appease the United States. Rather than doom many generations of South Asians to disaster, India and Pakistan should have relied on conventional weapons or relinquished Kashmir. Of course some countries will refuse to run such risks or make such sacrifices, but they do so at the expense of their own descendants.

Reliable Disarmament Is Not Possible
Whether states that already have nuclear weapons-including new arrivals such as India and Pakistan-should give them up is another matter. Even if nuclear states agreed to disarm, they might seek to rearm in a crisis. Whether conventional arsenals would be enough to deter a cheater from using nuclear weapons 88 is hard to judge. While a denuclearized world would have strong incentives to punish proliferation, 89 states would more probably themselves rearm when faced with a great power's cheating or rearmament than go to war to stop it. States in a rearmament race would likely have haphazard command and control, and a state that thought it had a lead might launch a preventive war. Nuclear disarmament could thus make nuclear war more likely rather than less. 90 As Charles Glaser notes, this is not an argument for proliferation by "nonnuclear states that cannot build nuclear weapons . . . within the timespan of a reasonably long conventional war." 91 Nor would it forbid disarmament if states are unable to rearm quickly. 92 In that case they should give up the bomb for the same reasons that non-nuclear states should not build it in the first place. Nevertheless, we could scarcely be confident that states could not rearm quickly in a crisis, particularly if they had concealed weapons or secretly continued research. The race between America and Nazi Germany to invent the bomb is not an encouraging precedent. For the foreseeable future, nuclear states seem stuck with the Faustian bargain. In this case, it is only fair for them to pay a larger share of the costs.

Minimum Deterrence
An ideal form of deterrence would target the inhabitants of Washington and Moscow, without endangering third-party countries, wild animals, the Library of Congress, or the future of the species. One might seek to achieve this, for example, by replacing present arsenals with enhanced radiation weapons aimed at cities. The neutron bomb is often accused of destroying people, not property, but from an international and intergenerational perspective this would be its greatest virtue. Americans and Russians would die in a war, but Brazilians, bears, and St. Basil's Cathedral would be spared. Unfortunately, relying on enhanced radiation weapons (ERW) will not work. Even neutron bombs, according to Carl Sagan, could start large fires which could contribute to nuclear winter. 93 In any case, cellars a few feet below ground could protect civilians from radiation. 94 Once simple measures of civil defense were adopted, ERW would no longer be a MAD deterrent.
Some analysts propose targeting military forces rather than cities, both to spare civilians and also because it would be less likely to bring on nuclear winter. While targeting an enemy's nuclear forces could prove destabilizing, attacking conventional targets need not be. 95 No such agreement, however, could be verified. Missiles can be retargeted within seconds. Even if leaders did not aim at cities and oilfields on purpose, in the fog of war they might strike some by accident or they might change their minds in the course of the war and escalate to attacking cities. Without deep cuts, a "counterpower" strategy still entails the risk of catastrophe. 96 A force comprised solely of many accurate but very low-yield warheads might limit damage but could still cause large fires, and the warheads' yield could be hard to verify. 97 Missile defenses, if they could be made to work, would avert the risks nuclear weapons pose both to present and future generations. Yet they face huge technical obstacles 98 and as long as there is no defense against weapons such as cruise missiles, cities can still burn, and nuclear winter remains a risk. 99 Combined with ambitious arms control, missile defenses could reduce the nuclear threat. 100 Without such measures, they are more likely to prove destabilizing. Similarly, reductions in warhead yield or a counterpower strategy could add security if accompanied with deep cuts in nuclear arsenals. 101 To rely on adoption of a counterpower strategy or on mini-nukes alone depends too much on states' good faith and rationality. Given the potentially catastrophic consequences if states should break the agreement, this is not a risk we ought to run.
Deterrence at very low numbers of nuclear weapons seems more promising. Disarmament does have two big advantages. It would limit the number of nuclear powers, even if states broke out of an agreement; 102 and while a rearmament race could make nuclear war more likely, states would probably fight before both had achieved secure second-strike deterrents-and thus with small numbers of weapons. 103 If disarmament led to rearmament and a limited nuclear war, however, things would not stop there. The survivors would most likely build large arsenals, and we would be back where we started, minus a handful of cities, a few million people, and any willingness to pursue either disarmament or minimum deterrence in the future. 104 Disarmament could thus increase the risk of catastrophe. Minimum deterrence lacks disarmament's advantage of limiting the spread of nuclear weapons, but the risk of war would be lower. Thus in the long term, states would be more likely to keep arsenals small enough to limit damage. 105 It is the more sustainable policy.

How Many is the Minimum?
For damage reduction to be meaningful, nuclear arsenals would have to be small indeed. Even most advocates of minimum deterrence have seen it as requiring hundreds if not thousands of warheads. 106 The logic of nuclear optimism, however, implies that we could go much lower. Waltz notes Bernard Brodie's statement that the USSR could be deterred with a single hydrogen bomb that could and would reliably be used on Moscow: "I would change that sentence by substituting 'might' for 'would,"' he remarks, "and by adding that the threat of a fission bomb or two would also do the trick." 107 Five warheads could wreck the Boston-Washington or San Diego-San Francisco corridors. Fifteen warheads could kill as many Russians as died in all of World War II. 108 As Stansfield Turner observes, to deter the Russians "probably takes the same number as it does to deter the United States-one. But let us play it safe. Call it five or ten, or some such number-still, it will not be in the hundreds or thousands." 109 We may need a few more weapons to ensure that some will survive and get through-but not more than a few. Even the chance that a couple of weapons might get through should deter attack. 110 "To locate virtually all missiles and aircraft is not good enough," Waltz observes. ". . . What political-military objective is worth risking Vladivostok, Novosibirsk, and Tomsk, with no way of being sure that Moscow would not go as well?" 111 A state run by zealots or lunatics may not be deterred, but fanatics are likely to be undeterrable anyway. 112 Are states actually this cost-and risk-averse? Roger Barnett points out that Germany and Japan fought on through World War II despite devastating bombing raids and that Iraq tolerated massive deaths from international sanctions. 113 The relevant questions, however, are whether German and Japanese leaders would have initiated war in 1941 knowing that they could lose half a dozen of their biggest cities and whether Saddam Hussein would have risked provoking a nuclear strike on Baghdad. 114 Moreover, supposing that they were willing to run such risks, is there reason to think a larger deterrent would have changed their minds? Barnett cites Muammar al-Qaddafi's claim that he would have struck New York in response to the bombing of Libya as evidence that leaders will accept huge losses, but if the Libyan dictator's words were anything more than bravado, they suggest that size does not matter, since he claimed to be willing to attack a state with a huge nuclear arsenal.
A stronger challenge comes from Keir Lieber and Daryl Press, who point out that as late as the 1960s U.S. officials seriously contemplated nuclear war against the Soviet Union. They argue that the mere possibility that the opponent will be able to retaliate may not be enough to deter a first strike. The Eisenhower Administration's strategy of "massive retaliation," they note, envisioned nuclear strikes in response to a Soviet invasion of Western Europe, and President Kennedy made inquiries about the possibility of a disarming strike on the USSR. 115 It has long been well-known, however, that U.S. officials made plans for the first use of nuclear weapons. They thought such plans necessary if the United States was to have a credible deterrent. The key question is whether they would ever have acted on them when they knew that an hour later nuclear weapons could be falling on Washington. Whether leaders will gamble on disarming the opponent if the odds seem good enough is, as Lieber and Press say, an empirical matter and deserves further investigation. 116 In any case, a minimum deterrent need not be vulnerable. Some see the risk that one side would cheat on arms agreements as a barrier to very deep cuts. 117 Strategically speaking, it is hard to see why cheating would matter unless a state thought it could destroy all the opponent's warheads. 118 China has made the most out of its arsenal by separating its missiles into small units. 119 Any advanced industrial power could ensure survivability by fielding multiple submarines, each armed with one or two warheads. 120 We can never be positive that force levels do not matter, but maintaining arsenals that threaten to wreck the world has its risks as well.
Carl Kaysen, Robert McNamara, and George Rathjens argue that "forces of a size and structure that would permit the destruction of, say, a dozen or a few tens rather than hundreds or thousands of targets in a retaliatory attack" should be as good deterrents as larger forces. 121 Harold Feiveson and his colleagues recommend a minimum deterrent of 200 warheads, though they observe that this "could nearly as easily be 400 or 100." 122 While war with 200 warheads each could still make World Wars I and II look like tussles in a sandbox, Sagan and Turco conclude that it would risk far less serious climatic consequences. 123 This creates a strong presumption in favor of deterrence at these levels, while continuing to explore the possibility of going still lower. Ironically, this is an agenda to which many nuclear optimists would agree.

Will Deep Cuts Encourage Proliferation?
Critics of minimum deterrence have also argued that it could encourage nuclear proliferation. If deep cuts required nuclear states to resume testing, this might indeed complicate non-proliferation efforts. 124 If the United States and Russia can test, states might ask, why shouldn't we? Minimum deterrence, however, should not require the resumption of testing. When many American experts testify that the Stockpile Stewardship Program ensures the U.S. deterrent's reliability, what enemy would be crazy enough to gamble? As Rajesh Basrur points out, "the adversary cannot assume that a risk is worth taking because the deterrer's weapons might not work. The potential consequences are not worth the risk." 125 Criticisms of the Comprehensive Test Ban Treaty (CTBT) on this ground have an air of unreality. As Senator John Kerry remarked during the CTBT debate: If you were offered the option 10 years from now or 20 years from now with our current mechanisms and verification capacities to take 20, 30. . . warheads out of our entire arsenal and we offered you the option of dropping them on North Carolina or Virginia, I guarantee you you would say please do not do that because you know as well as I do the better percentage of them are going to go off, if not all of them. . . . [Deterrence] is built on somebody's supposition that something might happen. 126 Some worry that minimum deterrence could encourage non-nuclear states to compete with Russia and the United States. 127 On the dominant model of nuclear proliferation, which holds that states acquire nuclear weapons in reaction to external threats, it is hard to see why the size of the Russian and American arsenals should matter. 128 Security-seeking proliferators, if they worry about survivability, will ask whether they can build a second-strike deterrent. A preventive or preemptive U.S. strike would involve small numbers of warheads, if nuclear weapons were used at all. A rational security-seeker contemplating proliferation will thus not care whether the great powers have three hundred or three thousand warheads. 129  129 Reasoning along the lines discussed in the following paragraph, a proliferator might conceivably conclude that great powers with a minimum deterrent lacked sufficient spare weapons to use in a preventive attack. It could never be sure, however, just how many weapons these powers saw as the bare minimum they must retain for deterrence-and hence how many they could spare-and in any case, as I argue in the next paragraph, discouraging proliferation is not sufficient grounds for retaining enormous arsenals. other hand, states seek nuclear weapons as a source of prestige, minimum deterrence might make proliferation more attractive by allowing small states to have as many as the great powers. By signaling that nuclear weapons are bad and that the powers were trying to kick the habit, however, it could also discourage proliferation. 130 Critics of minimum deterrence also argue that it could promote proliferation among America's allies. These might fear that Washington would not use a small arsenal unless the U.S. homeland came under attack. 131 In fact it is hard to imagine any aggressor so reckless as to gamble on this assumption, given the cost of being wrong. Still, worst-case thinking might lead Germany, Japan, Taiwan, or others to nuclearize. That would be too bad. The more states with nuclear weapons, the more chances that they will be used. In at least one case-Taiwan-proliferation could also lead to preventive war. Still, we should prefer a world with a higher risk of war but a lower risk of apocalyptic destruction. In such a world we pay more of the costs of our defense and externalize fewer to future generations.
Some disarmament advocates argue that only the complete abolition of nuclear weapons can delegitimate their acquisition. They believe that continued reliance on nuclear deterrence-even at low levels-will ensure proliferation, but while a "low salience nuclear world" of few nuclear powers with minimum deterrents may not be sustainable, 132 a world of many small nuclear powers might be. If states accept the logic of minimum deterrence, they should not depart from this equilibrium. What would either an aggressor or a defender gain from an arms build-up? While such a world would not be ideal, it would be better than the status quo-and more likely to be a stable solution than a premature attempt at nuclear disarmament.
In any case, for now, steps toward minimum deterrence are also steps toward disarmament. So long as the latter remains our ultimate objective, deep cuts can only help legitimate the nuclear non-proliferation regime. As Ken Booth and Nicholas Wheeler observe, "because we do not yet know how to get rid of the last few hundred warheads is not a sufficient reason for not going in that direction." 133 if minimum deterrence proves less stable will be a small nuclear war-still better than the large nuclear war that we can expect at present. Liberals, Marxists, and constructivists, on the other hand, may argue that the best way to escape nuclear deterrence altogether is to change the character of international politics. 134 This raises a potential objection to my argument. Perhaps today's apparently fairly stable form of deterrence is just what we need for peace-inducing phenomena such as democratization, economic interdependence, and integration to take hold. Kenneth Oye, for example, holds that the prolonged superpower standoff of the Cold War led to the Soviet Union's liberalization. 135 A premature attempt at minimum deterrence could interrupt long-term peace-inducing processes, 136 harming future generations as well as ourselves.
This objection should be taken seriously. However, if Russia and the United States should appeal to hopes for long-term progress toward peace to justify their huge arsenals, they ought to be working much harder to bring it about. Democratic peace theory is the single most powerful liberal theory of peace. Many liberals agreed that it was vital for international peace that Russia make a successful transition to liberal democracy, but U.S. spending on direct democracy assistance after the Cold War was paltry, amounting to $16 million in fiscal year 2000 for all of Russia. This was transparently "assistance on the cheap." 137 Nor, of course, has Russia itself done better: The Putin government's failure to promote democracy requires no commentary. One way or another, Washington and Moscow are falling down on their obligations-either to make deep cuts now or to create conditions for future disarmament.
Moreover, the possibility of radical change in international relations suggests that Britain and France have reason to consider nuclear disarmament. If the norms model of nuclear proliferation is right it could set a good example, discouraging the spread of nuclear weapons around the world. 138 True, if major change does not occur, London and Paris will someday face a confrontation in which they will be tempted to rearm. If they do so before being defeated this could mean nuclear war, but for Britain and France the risk seems remote. It is hard even to guess with what rival that crisis would be. Over the next century the spread of democracy, international integration, or other change may transform international relations before a confrontation involving either state recurs. This strengthens the case for these two states taking a chance on nuclear disarmament. The non-proliferation benefits may outweigh the risk that rearmament will lead to war in a crisis.

BETWEEN DEATH AND A GRIEVOUS WOUND
Most people think the risk of holocaust evaporated with the end of the Cold War, and the biggest nuclear threat comes from "rogue states" and terrorists. Most people are wrong. Losing a city or two will be horrible; a great power war may mean curtains for nearly all of us. While the chance of intentional world war is very low, the risk of accidental war remains. Indeed, with the decay of Russia's command, control, and communications, it has probably risen. Even if the West has reached the "end of history," with war among stable liberal democracies seeming all but impossible, this is not true of the rest of the world, 139 including some powerful states with nuclear weapons. To think that we can get through even a century without serious great power rivalry is to discount all of modern history. Certainly, leading nuclear optimists do not believe this. If our present reliance on huge arsenals were the best realism had to offer, one could only agree that "no serious thinker could . . . be satisfied with Realism . . . even if the scientific status of the theory were stronger than it is" 140 -for it would be a death sentence.
In fact, neorealist optimism suggests a partial escape: minimum deterrence. States that have not begun developing nuclear weapons should not start. "If deterrence works in the West," asks Jaswant Singh, "as it so obviously appears to, since Western nations insist on continuing to possess nuclear weapons-by what reasoning will it not work in India?" 141 In reality, nuclear deterrence has only worked so far-and only because we were lucky. Indians and Pakistanis who take pride in their bombs plume themselves on what will wreck their cities and kill their descendants. Still more important, states with bloated arsenals should slim them. Neorealists should want states to slash their arsenals even if it makes war more likely. As Paul Doty says, "The great gap . . . is . . . between a grievous but recoverable wound and death to most of the world as we know it." 142 On a liberal, Marxist, or constructivist analysis, a failed attempt at minimum deterrence could conceivably shortcircuit trends that can make war obsolete. Even if so, nuclear states can only justify large arsenals by working much harder to create conditions for their abolition.
This article has argued that nuclear optimism should lead us to support nuclear nonproliferation as well as deep cuts in arsenals and-if it is ever feasible-disarmament. Some pessimists hold that organizational routines, bureaucratic politics, and bounded rationality make control over nuclear weapons less reliable than optimists claim. If so, this only reinforces my prescriptions. Not only is the spread of nuclear weapons a bad thing, but it is yet another reason for Russia and the United States to downsize their arsenals to more manageable levels. 143

Motivating Just Behavior
All these arguments may seem academic. Suppose nuclear deterrence does exploit future generations-can any state be expected to renounce it? Nuclear war is one of many threats that humans pose to nature. 144 Yet when the threat is not concrete, it is easy to ignore the problem and hope that it is exaggerated, or will somehow go away. 145 Global warming is starting, but will take some time to make itself felt. Likewise, nuclear weapons may not make themselves felt at all until it is too late. 146 Faced with what activists believe is a threat to the very future of life on earth, mass publics remain infuriatingly complacent. 147 Theorists, seeing that nuclear deterrence seems to benefit us, take for granted that it also benefits our distant descendants. This is not surprising, since, as E. H. Carr says, "the doctrine of the harmony of interests . . . . is the natural assumption of a prosperous and privileged class." 148 Moreover, if the status quo benefits us, what is our incentive to act? By debunking the harmony of interests, Carr did not expect to turn the privileged For states that have already nuclearized, going down to minimum deterrents may not cost anything. It will probably reduce the risk of accidental war, 160 while lowering the costs when war eventually breaks out. Waltz and his followers have made a strong case that nuclear weapons are superb deterrents. As Waltz himself recognizes, this means that just a few should be enough.