CLIMATE CHANGE JUSTICE
(WITH ERIC A. POSNER)
The problem of climate change raises difficult issues of science, economics, and justice. Of course, the scientific and economic issues loom large in public debates, and they have been analyzed in great detail. By contrast, the question of justice, while also playing a significant role in international debates, has received less sustained attention.
Several points are clear. The United States, which long led the world in greenhouse gas emissions, has been surpassed by China. The two leading emitters now account for over 40 percent of the world’s emissions, but they have independently refused to accept binding emissions limitations, apparently because of a belief, on the part of influential political leaders, that the domestic costs of such limitations would exceed the benefits. President Obama did support a national cap-and-trade program, which was passed by the House of Representatives in 2009, but the Senate refused to act on it, and as of this writing, such a program does not appear likely to be enacted in the near future.
The emissions of the United States and China threaten to impose serious economic and environmental losses on other nations and regions, including Europe, India, and Africa. For this reason, it is tempting to argue that both nations are, in a sense, engaging in wrongful acts against nations that are most vulnerable to climate change. This argument might seem to have special force as applied to the actions of the United States. While its emissions are growing relatively slowly, and while China’s are growing rapidly, the United States remains the largest contributor to the existing stock of greenhouse gases. Because of its past contributions, does the United States owe remedial action or material compensation to those nations, or those citizens, most likely to be harmed by climate change? Principles of corrective justice might seem to require that the largest emitting nation pay damages to those who are hurt—and that they scale back their emissions as well.
Questions of corrective justice are entangled with questions of distributive justice. The United States has the highest gross domestic product of any country in the world, and its wealth might suggest that it has a special duty to help to reduce the damage associated with climate change. Are the obligations of the comparatively poor China, the leading emitter, equivalent to those of the comparatively rich United States, the second-leading emitter? Does it not matter that the per capita emissions of China, which has more than four times the population of the United States, remain a small fraction of those of the United States? Perhaps most important: because of its wealth, should the United States be willing to sign an agreement that is optimal for the world as a whole—but not optimal for the United States?
The goal of this chapter is to answer these questions. Let us start with two reasonable but admittedly controversial assumptions.
First, the world, taken as a whole, would benefit from an agreement to reduce greenhouse gas emissions. This assumption is reasonable because mounting evidence suggests that the global benefits of imaginable steps—such as a modest worldwide carbon tax, growing over time—are significantly greater than the global costs.
Second, some nations, primarily the United States (and China as well), might not benefit, on net, from the agreement that would be optimal from the world’s point of view. Suppose, for example, that the world settled on a specified carbon tax—say, $60 per ton. Such a tax would likely impose especially significant costs on the United States, simply because its per capita emissions rate is so high. Suppose, too, that America is less vulnerable to the serious health and agricultural consequences of climate change than are many other nations, such as India and sub-Saharan Africa.1 Perhaps the optimal carbon tax, for the world, would be $60 per ton, but the United States would do better with a worldwide carbon tax of $40 per ton, or $30 per ton, or even $20 per ton.
If so, the standard resolution of the problem is clear: the world should enter into the optimal agreement, and the United States should be given side payments in return for participating. The reason for this approach is straightforward. The optimal agreement should be assessed by asking about the overall benefits and costs of the relevant commitments for the world. To the extent that the United States is a net loser, the world should act so as to induce it to participate in an agreement that would promote the welfare of the world’s citizens, taken as a whole. With side payments to the United States (of the kind that have elsewhere induced reluctant nations to join environmental treaties), an international agreement could be designed so as to make all nations better off and no nation worse off. Who would oppose such a treaty?
A serious puzzle is that almost everyone does! No one is suggesting that the world should offer side payments to the United States. Indeed, even the United States is not insisting on side payments, perhaps on the grounds that the demand would be regarded as preposterous. One reason involves distributive justice. Many people would find it odd to suggest that the world’s richest nation should receive compensation for helping to solve a problem faced by the world as a whole—and above all by poor nations.
On this view, wealthy nations should be expected to contribute a great deal to solving the climate change problem; side payments would be perverse. If we care about distributive justice, it might seem far more plausible to suggest that nations should pay China to take part in a climate change agreement. And indeed, developing nations, including China, were given financial assistance as an inducement to reduce their emissions of ozone-depleting chemicals. Some people think that a climate change agreement should build on this precedent; but no one seems to think that payments should go to the United States.
But claims about distributive justice are only part of the story. Corrective justice matters as well. The basic thought is that the largest emitters, including the United States, have imposed serious risks on other nations. Surely it cannot be right for nations to request payments in return for ceasing to harm others. Many people think that wrongdoers should pay for the damage that they have caused and should be asked to stop.
This chapter will raise serious questions about both accounts. There is a strong argument that rich nations and rich people should give resources to poor nations and poor people. But significant greenhouse gas reductions are not the best way of attempting to achieve redistributive goals. The arc of human history suggests that in the future, people are likely to be much wealthier than people are now. Why should wealthy countries give money to future (less) poor people rather than to current poor people?
In any case, nations are not people; they are collections of people. Redistribution from wealthy countries to poor countries is hardly the same as redistribution from wealthy people to poor people. Poor people in wealthy countries may well pay a large part of the bill for emissions reduction. A stiff tax on carbon emissions could have particularly severe effects on poor people, at least if steps are not taken to compensate them.
The upshot is that if wealthy people in wealthy nations want to help poor people in poor nations, emissions reductions are unlikely to be the best means by which to do so. A puzzle, then, is why many people take distributive justice to require wealthy nations to help poor ones in the context of climate change, when wealthy nations are not being asked to help poor ones in areas in which the argument for help is significantly stronger.
The discussion here will also accept, for purposes of argument, the view that when people in one nation wrongfully harm people in another nation, the wrongdoers have a moral obligation to provide a remedy to the victims. It might seem to follow that the largest emitters, and especially the United States, have a special obligation to remedy the harms they have caused (and certainly should not be given side payments). But this argument runs into serious problems. Nations are not individuals: they do not have mental states and cannot act, except metaphorically. Blame must ordinarily be apportioned to individuals.
If the United States wants to assist poor nations, reducing its greenhouse gas emissions is unlikely to be the best way to accomplish that goal. It is true that many people in poor nations are at risk because of the actions of many people in the United States, but the idea of corrective justice does not easily justify any kind of transfer from contemporary Americans to people now or eventually living in, say, India and Africa.
This conclusion should not be misunderstood. Nothing said here questions the proposition that an international agreement to control greenhouse gases, with American participation, is justified. Moreover, it is good if wealthy countries are willing to help vulnerable people in poor ones. Consider the example of genocide. If a nation could prevent genocide at a modest cost to itself, it should do so, even if that nation is a net loser. The goal here is not to question these propositions, or to suggest any particular approach to the climate change problem, but to show that contrary to widespread beliefs, standard ideas about distributive or corrective justice poorly fit the climate change problem.
There is voluminous literature on the science and economics of climate change. Let us concentrate on the facts that are most relevant to the questions of justice.
As noted, there is strong agreement with the view that the world would benefit from significant steps to control greenhouse gas emissions. If all of the major emitting nations agreed to such steps, the benefits would almost certainly exceed the costs. To be sure, there is continuing disagreement about the appropriate timing and severity of emissions reduction; perhaps aggressive reductions are justified in the near future. But as compared with “business as usual,” much would be gained, and less lost, if at least some reduction policies were adopted soon, followed by larger ones over time.
There is also much agreement that if the world does undertake an effort to reduce greenhouse gas emissions, it should select one of two possible approaches.2 The first is an emissions tax, designed to capture the externalities associated with climate change. A worldwide tax on carbon emissions might start relatively low—perhaps $10 per ton—and increase as technology advances. With this approach, it is generally assumed that the tax would be uniform. Citizens of Russia, China, India, the United States, France, and so forth would all pay the same tax, on the theory that the relevant amount reflected the social cost of the emissions. There is disagreement about the proper magnitude of the tax, and, as we shall see, different nations would gain and lose different amounts from any specified tax.
The second approach involves a system of cap and trade, under which nations might create a worldwide cap on aggregate emissions—calling for, say, a 3 percent reduction in worldwide emissions to start, with further reductions over time. A cap-and-trade system would require judgments about the appropriate cap as well as an initial allocation of emissions rights. In one version, existing emissions levels would provide the foundation for initial allocations; countries would have to reduce those existing levels by a certain percentage. The use of existing levels is highly controversial and, in a sense, arbitrary. But analytically, it is not very different from a uniform carbon tax; in both cases, current practices are the starting point for regulatory measures.
It is critical to see that an agreement to control greenhouse gas emissions would be most effective only if all or most of the major nations participate. If the United Kingdom, France, or Germany stabilized its emissions rate at 1995 levels, aggressive cuts by each would be required, but the effect on warming would be modest. One reason is the large existing stock of greenhouse gases; another is that global increases in greenhouse gas emissions would not be much affected if only one of those three countries stabilized its emissions. If the developed world acts while developing nations refuse to accept any emissions restrictions, the actual effect on anticipated warming will not be trivial, but it will be very far from what is required.
EMITTERS
To understand the issues of justice and the motivations of the various actors, it is important to appreciate the disparities in emissions across nations. We do not have clear data on the costs of emissions reduction for different nations, but it is reasonable to predict that the largest carbon emitters would bear the largest burdens from, say, a worldwide carbon tax.
As noted, the United States and China are the world’s largest emitters, and China’s emissions are growing at a truly explosive rate. Estimates suggest that the largest contributors are likely to continue to qualify as such but that major shifts will occur, above all with emissions growth in China and India. Next to China and America, the countries that have produced the highest emissions are India, Russia, Japan, and Germany. Projections are in considerable flux, but by 2030, the developing world is expected to contribute at least 55 percent of total emissions, with at most 45 percent coming from developed nations. All by itself, China may well produce over half of the world’s emissions before long.
These are points about flows: how much a given nation emits on an annual basis. Also relevant for claims of justice are the stocks: how much a given nation has, over time, contributed to the current accumulation of greenhouse gases in the atmosphere. The United States is the highest-ranked contributor, while China remains a distant fourth, and India is ninth.
The reason for the disparity is that greenhouse gases dissipate very slowly, so countries that industrialized earlier have contributed more to the stock than countries that industrialized later, even though today the latter group might contribute more on an annual basis. Carbon dioxide (CO2) is the most important greenhouse gas, and about half of the CO2 emitted in 1907 still remains in the atmosphere.3 If the world suddenly stopped emitting CO2 today, the stock of CO2 in the atmosphere in 2107 would remain at about 90 percent of what it is now. This point matters greatly. It helps to explain why even significant emissions reduction will bring down anticipated warming but hardly halt it. We are now in a better position to see why unilateral action, even by the largest emitters, will accomplish relatively little. Such action cannot affect the existing stock, and by definition, it will do nothing directly about the rest of the flow.
VICTIMS
Which nations are expected to suffer most from climate change? The precise figures are greatly disputed. The extent of the damage in 2050 or 2100 cannot be predicted now, in part because of insufficient information about each country’s ability to adapt to warmer climates. But it is generally agreed that the poorest nations will be the biggest losers by far.4 The wealthy nations, including the United States, are in a much better position, for three independent reasons.5 First, they have much more in the way of adaptive capacity. Second, a smaller percentage of their economies depend on agriculture, a sector that is highly vulnerable to climate change. Third, the wealthy nations are generally in the cooler, higher latitudes; this also decreases their vulnerability.
To be sure, any specific estimates must be taken with many grains of salt; they are at best only suggestive. Because regions are economically interdependent, significant adverse effects on India, Africa, and Europe would surely have a major impact on the United States, China, and Russia. But it is readily apparent that some nations are far more vulnerable than others.
India, for example, is expected to experience devastating losses in terms of both health and agriculture. In terms of health effects alone, the country has been projected to lose 3.6 million years of life from climate-related diseases such as malaria.6 For Africa, the major problem involves health, with a massive anticipated increase in climate-related diseases.7 Sub-Saharan Africa has been projected to lose 26.7 million years of life due to climate-related diseases, with 24.4 million coming from malaria.8 The United States faces significant but more limited threats to both agriculture and health.
From these very brief notes, it seems useful to analyze the questions of justice by assuming that (1) the world would benefit from an agreement to control greenhouse gas emissions; (2) the United States would have to pay a significant amount to reduce its emissions; (3) some nations would benefit far more than others from worldwide reductions; and (4) the United States would not be the largest beneficiary and could possibly even turn out to be a net loser from a large uniform carbon tax or from a cap-and-trade program that requires very major reductions from existing emissions levels. A primary question is how to understand the moral obligations of the United States; also of interest are the proper approaches of and toward China.
CLIMATE CHANGE AND DISTRIBUTIVE JUSTICE
To separate issues of distributive justice from those of corrective justice, let us begin with a risk of natural calamity that does not involve human action at all.
THE ASTEROID
Imagine that India faces a serious new threat, in the form of impact from an asteroid. Imagine, too, that this potentially cataclysmic event will not materialize for a century. Finally, imagine that the threat can be eliminated today, but at such a high cost that it would devastate the country. As a practical matter, India lacks the resources to take the steps necessary to prevent the asteroid strike. But if the nations of the world act in concert, they can begin to build technology that will allow them to divert the speeding space rock, thus insuring that it does not collide with India a century hence. The cost is high, but it is lower than the discounted benefit of eliminating the threat. If the world delays, it might still be able to eliminate the threat or reduce the damage if the asteroid does strike. But many scientists believe that the best approach, considering relevant costs and benefits, is to start immediately to build technology that will divert the asteroid.
Are wealthy nations, such the United States, obliged to contribute significant sums of money to protect India from the asteroid? On grounds of distributive justice, it is certainly tempting to think so. But if we do reach that conclusion, how should we deal with India’s contention that it could avert millions of premature deaths from disease and malnutrition if the United States came to its aid with some small fraction of the US gross domestic product? If one nation is threatened by malaria or a tsunami, other nations might well agree that it is appropriate to help; it is certainly honorable to assist those in need. But even altruistic countries do not conventionally think that a threatened nation receives their assistance as a matter of entitlement. To be sure, there are some philosophical puzzles here, but for those who believe that there is such an entitlement, the puzzle remains: Why is there an entitlement to help in the event of future harm from an asteroid, rather than to help to avert current harms?
True, the problem of the asteroid threat differs significantly from that of climate change, whose adverse effects are not limited to a single nation. To make the analogy closer, let us suppose that all nations are threatened by the asteroid, in the sense that it is not possible to project where the collision will occur. Scientists believe that each nation faces a risk. But the risk is not identical. Because of its adaptive capacity, its location, its technology, and a range of other factors, let us stipulate that the United States is less vulnerable to serious damage than are India and the nations of Africa and Europe. Otherwise the problem is the same. Under plausible assumptions, the world will certainly act to divert the asteroid, and it seems clear that the United States will contribute substantial resources for that purpose.
In this scenario, all nations favor an international agreement requiring contributions to a general fund. But because the United States is less vulnerable, it believes that the fund should be smaller than the one supported by countries in greater danger. From the standpoint of domestic self-interest, then, those nations with the most to lose will naturally seek a larger fund than those facing lower risks.
At first glance, it might seem intuitive that the United States should accept the proposal for the larger fund, simply because it is so wealthy. If resources should be redistributed from rich to poor, on the ground that redistribution would increase overall welfare or promote fairness, the intuition appears sound. But there is an immediate problem. If redistribution from rich nations to poor nations is generally desirable, it is not at all clear that it should take the particular form of a deal in which the United States joins an agreement that is not in its interest. Other things being equal, the more sensible kind of redistribution would be a cash transfer, so that poor nations can use the money as they see fit. Perhaps India would prefer to spend the money on education, or on AIDS prevention, or on health care in general. If redistribution is what is sought, a generous deal with respect to the threat of an asteroid collision seems a crude way of achieving it.
A second difficulty is that the asteroid will not hit Earth for another hundred years. If the world takes action now, it will be spending current resources for the sake of future generations, which are likely to be much richer. The current poor citizens of poor nations are probably much poorer than will be the future poor citizens of those nations. If the goal is to help the poor, it is odd for the United States to spend significant resources to help posterity while neglecting the present. Thus far, then, the claim that the United States should join what seems, to it, to be an unjustifiably costly agreement to divert the asteroid is doubly puzzling. Poor nations would benefit more from cash transfers, and the current poor have a stronger claim to assistance than the future (less) poor.
From the standpoint of distributive justice, there is a third problem. Even wealthy countries such as the United States have many poor people, just as poor countries such as India have many rich people. If the United States is paying a lot of money to avert the threat of an asteroid strike, it would be good to know whether that cost is being paid, in turn, by wealthy Americans or by poor Americans. Suppose, for example, that greenhouse gas reductions lead to a significant increase in energy costs. Any such increase—either from carbon taxes or from cap and trade—would be regressive, in that it would hit the poor harder than the wealthy. True, products should be priced at their full social cost, and an externality-correcting tax would have strong justifications here as elsewhere. But if the concern is to help people who need help, such a tax is hard to defend.
Because the median members of wealthy nations are wealthier than the median members of poor nations, it is plausible to think that if wealthy nations contribute a disproportionally high amount to the joint endeavor, the redistribution of wealth will be not be entirely ineffective. Americans who are asked to make the relevant payments are, on average, wealthier than the Indians who are paying less. But asking Americans to contribute more to a joint endeavor is hardly the best way of achieving the goal of transferring wealth from the rich to the poor.
CLIMATE CHANGE: FROM WHO TO WHOM?
In terms of distributive justice, the problem of climate change is analogous to the asteroid problem, in the sense that it raises three questions:
1. Why should redistribution take the form of an in-kind benefit rather than a general monetary grant that poor nations could use as they wish?
2. Why should rich nations help poor nations in the future rather than poor nations now?
3. If redistribution is the goal, why should it take the form of action by rich nations that might turn out to hurt many poor people?
To sharpen these questions, suppose that an international agreement to cut greenhouse gas emissions would cost the United States $325 billion. If distributive justice is the goal, should America spend the money on climate change or on other imaginable steps to help people in need? In fact, the distributive justice argument is especially weak in the case of climate change. No one would gain from an asteroid collision, but millions of people are benefiting, and will benefit, from climate change. Many people die from cold, and to the extent that warming reduces cold, it will save lives. Warming will also produce monetary benefits in many places, mainly as a result of increased agricultural productivity in countries such as Russia.9 Many millions of rural Chinese continue to live in poverty despite the country’s increasing prosperity as a whole. These people are among the poorest in the world. For at least some of them, climate change could well provide benefits by increasing agricultural productivity. In addition, many millions of poor people would bear the burdensome cost of emissions reduction in the form of higher energy bills, lost jobs, and increased poverty.
None of this means that climate change is in the world’s interest; it is not. And to be sure, a suitably designed emissions reduction agreement would almost certainly help poor people more than it would hurt them, because disadvantaged people in Africa and India are at such grave risk. From the standpoint of distributive justice, such an agreement might well be better than the status quo. The only point is that there is a highly imperfect connection between distributive goals on the one hand and requiring wealthy countries to pay for emissions reduction on the other.
TWO COUNTERARGUMENTS
There are two tempting counterarguments. The first involves the risk of catastrophe. The second involves the fact that cash transfers will go to governments that may be ineffective or corrupt.
Catastrophe. On certain assumptions about the science, greenhouse gas reductions are necessary to prevent a catastrophic loss of life.10 Suppose, by way of imperfect analogy, that genocide is occurring in some nation. For multiple reasons, it would not be sensible to say that rich countries should give that country financial assistance rather than act to prevent the genocide. Or suppose that a nation is threatened by a natural disaster that would wipe out hundreds of thousands of lives. If other nations could somehow eliminate the harms associated with such a disaster, it would be hard to object that they should offer cash payments instead. One reason is that if many lives are at risk, and they can be saved through identifiable steps, taking those steps would seem to be the most direct and effective response to the problem, while cash transfers would have little or no advantage.
Suppose that climate change threatens to create massive losses of life in various countries. In light of the risk of catastrophe, perhaps emissions reductions are preferable to other redistributive strategies. The catastrophic scenario is a way of saying that the future benefits of cuts in greenhouse gases could be exceptionally high rather than merely very high. If poor people in poor nations face a serious risk of catastrophe, then greenhouse gas abatement could turn out to be the best way to redistribute wealth (or, more accurately, welfare) to people who would otherwise die in the future.
Ultimately the strength of the argument turns on the extent of the risk, based on the scientific evidence. If it is high, and faced mostly by people living in difficult or desperate conditions, the distributive justice argument gains a great deal of force.
Ineffective or Corrupt Governments. As noted, development aid is likely to be more effective than greenhouse gas restrictions as a method of helping poor people in poor nations. But a legitimate argument for cutting greenhouse gas emissions is that this step bypasses the governments of poor states more completely than other forms of development aid do. This might be counted as a virtue because the governments of some poor states are, to a large degree, either inefficient or corrupt (or both), and partly for that reason, ordinary development aid has not always been effective.
At the same time, this form of redistribution does not, as we have stressed, help existing poor people at all; it can, at best, help poor people in the future. In addition, the claim that emissions reduction avoids political inefficiency or corruption overlooks the fact that emissions abatement does not occur by itself; it must take place through the activity of governments. In cap-and-trade systems, for example, the government of a poor country would be given permits, which it could then sell to industry, raising enormous sums of money that the government could spend however it chose. A corrupt or disreputable government might not spend this money to benefit its people. On the contrary, it might use the money to finance political repression, while also possibly accepting bribes from local industry that chooses not to buy permits, in return for nonenforcement of the country’s treaty obligations. These points are speculative, to be sure, but they suggest that the risks associated with inefficient or corrupt governments cannot easily be avoided.
PROVISIONAL CONCLUSIONS
There are reasonable arguments to support the view that people in rich countries should be giving money to help people in poor ones. There are reasonable arguments on behalf of a uniform carbon tax. There are also reasonable arguments on behalf of a worldwide cap-and-trade program, designating existing emissions rates as the starting point. What is puzzling is the claim that on grounds of distributive justice, the best approach is for the United States to join an agreement that is not in its interest rather than to take more direct steps to help those who need it.
It is true, however, that if America does spend a great deal on emissions reduction as part of an international agreement, and if the agreement does give particular help to disadvantaged people, considerations of distributive justice support its action, even if better redistributive mechanisms are imaginable. It is even possible that desirable redistribution is more likely to occur through climate change policy than otherwise, or is likely to be accomplished more effectively through climate policy than through direct foreign aid.
The only claims are that aggressive emissions reductions on the part of the United States are not an especially effective method for transferring resources from wealthy people to poor people, and that if this is the goal, many alternative policies would probably be better. It should be clear that these claims apply broadly to efforts to invoke distributive justice to ask wealthy nations to participate in international agreements from which other nations might gain.
CORRECTIVE JUSTICE
Climate change differs from the asteroid example in another way. In the asteroid scenario, no one can be blamed for the fact that the asteroid is hurtling toward Earth and the threat that it poses to India (or the world). But many people believe that by virtue of its past actions and policies, the United States, along with other developed nations, is particularly to blame for the problem of climate change.
Corrective justice arguments are backward looking, focused on wrongful behavior that occurred in the past. They require us to look at stocks rather than at flows. Of course, a disproportionate share of the stock of greenhouse gases can be attributed to other long-industrialized countries as well, such as Germany and Japan, and so what is said here about the United States can be applied to those other countries too.
In the context of climate change, the corrective justice argument is that the United States has wrongfully harmed the rest of the world—especially low-lying states and others that are most vulnerable—by emitting greenhouse gases in vast quantities. Many people believe that corrective justice requires America to devote significant resources to remedy the problem. India, for example, might be thought to have a moral claim against the United States, one derived from the principles of corrective justice, and on this view, the United States has an obligation to provide a compensatory remedy to India. (Because India is especially exposed to climate change, that nation can be used as a placeholder for those at particular risk.)
This argument enjoys a great deal of support in certain circles and seems intuitively correct. The apparent simplicity of the argument, however, masks some serious difficulties. The most general point, summarizing the argument as a whole, is that the climate change problem fits the corrective justice model poorly, because the consequence of such thinking would be to force many people who have not acted wrongfully to provide a remedy to many people who have not been victimized.
THE WRONGDOER IDENTITY PROBLEM
The current stock of greenhouse gases in the atmosphere is a result of the behavior of people from the past. Many of them are now dead. The basic problem for corrective justice is that dead wrongdoers cannot be punished or held responsible for their actions, or forced to compensate those they have harmed. At first glance, holding Americans today responsible for the activities of their ancestors is not fair or reasonable on corrective justice grounds.
The best response to this point is to insist that all or most Americans today benefit from the emissions activities of US citizens from the past, and therefore it would not be wrong to require Americans today to pay for abatement measures. This argument is familiar from debates about slave reparations, where it has been argued that Americans today have benefited from the toil of slaves one hundred fifty years ago. To the extent that members of current generations have gained from past wrongdoing, it may well make sense to ask them to compensate those harmed as a result. On one view, compensation can help to restore the status quo ante—that is, put members of different groups in the positions they would have occupied if the wrongdoing had not occurred.
But this argument runs into serious problems. In the context of climate change, the most obvious difficulty is empirical. How many US citizens benefit from past climate change emissions, and how much do they benefit? Many Americans today are, of course, immigrants or children of immigrants, and therefore are not the descendants of greenhouse-gas-emitting Americans of the past. Nonetheless, such people may benefit from past emissions, because they enjoy the kind of technological advances and material wealth that those emissions made possible. But have they actually benefited, and to what degree? Further, not all Americans inherit their wealth, and even those who do would not necessarily have inherited less if their ancestors’ generations had not engaged in the greenhouse-gas-emitting activities.
Suppose that these obstacles could be overcome and that we could trace, with sufficient accuracy, the extent to which current Americans have benefited from past carbon emissions. As long as the costs are being totted up, the benefits should be as well, and used to offset the requirements of corrective justice. If past generations of Americans have imposed costs on the rest of the world, they have also conferred substantial benefits. American industrial activity has produced products that are (and have long been) consumed in foreign countries, and helped produce technological advances from which citizens in other countries have greatly benefited.
True, many citizens in other nations have not benefited much from those advances, just as many citizens of the United States have benefited little from them. But what would the world, or India, look like if America had engaged in 10 percent of its level of greenhouse gas emissions, or 20 percent, or 40 percent? For purposes of corrective justice, a proper accounting would seem to be necessary, and it presents formidable empirical and conceptual problems.
THE CULPABILITY PROBLEM
Philosophers disagree about whether corrective justice requires culpability.11 Intentional, reckless, or negligent action is usually thought to be required for a corrective justice claim. Because multiple persons and actions (including actions of the victim) are necessary for harm to have occurred, identification of the person who has “caused” the harm requires some assignment of blame. At a minimum, the case for a remedy is stronger when a person acts culpably rather than innocently, and so it is worthwhile to inquire whether the United States or Americans can be blamed for contributing to climate change. The idea that Americans are to blame by contributing excessively to climate change is an important theme in international debates.
Negligence. The weakest standard of culpability is negligence. If you negligently injure people, you owe them a remedy. Economists define negligence as the failure to take cost-justified precautions. Lawyers tend to appeal to community standards.
Today the scientific consensus holds that the planet is warming and that this warming trend is due to human activity. But the consensus took a long time to form. Greenhouse-gas-emitting activities could not have been negligent, under existing legal standards, until a scientific consensus formed and it became widely known among the public—a relatively recent occurrence.12
Even today, it is not clear when and whether engaging in greenhouse gas emitting activities is properly characterized as negligent. Suppose that a large company in New York emits a large volume of greenhouse gases. Is it negligent? It is easily imaginable that the costs of emissions abatement would be significant; it is clear that the benefits of emissions abatement, in terms of diminished warming, would be very low. Heating a house, driving a car, running a freezer, taking an airplane—are all of these activities negligent? Even though the warming effects of the relevant emissions are essentially nil? Recent work tries to identity a “social cost of carbon”; in the United States, the central value is now around $37.13 Perhaps we could use that value to test the question of negligence. But if so, a great deal of activity that involves greenhouse gas emissions would not count as negligent.
Negligent Government? What about the US government? The argument would be that the government failed to take precautions that would have cost it a lot but benefited the rest of the world much more.
In the context of climate change, the problem is that, as noted above, it is not clear that America could have taken unilateral action that would have created benefits for the rest of the world greater than the cost to the United States. Unilateral reductions in greenhouse gas emissions would not have a large effect on overall climate change. Use of the social cost of carbon might help, but here, as in the case of individuals, a great deal of emissions activity would not be defined as negligence.
However appealing, corrective justice intuitions turn out to be a poor fit with the climate change problem—where the dispute is among nations, and where an extremely long period of time must elapse before the activity in question generates harm. This is not to say that a corrective justice argument cannot be cobbled together and presented as the basis of a kind of rough justice in an imperfect world. But such an argument would rely heavily on notions of collective responsibility that are not so easy to defend.
PER CAPITA EMISSIONS
Along with other developing nations, China has urged that the analysis ought to focus on a nation’s per capita emissions, not its aggregate emissions.14 This argument might even be linked to a general “right to development,” on the theory that a worldwide carbon tax (for example) would make it harder for poor nations to achieve the levels of development already attained by wealthy nations. Perhaps an imaginable climate change agreement, one that would actually be effective and efficient, would violate the right to development.
With respect to China, the factual predicate for this argument is that its population is the largest on the planet. Notwithstanding its truly explosive emissions growth, the country’s per capita emissions remain well below those of many nations. China has contended that its relatively low per capita emissions rate—below not only the United States but also Japan, India, Russia, Germany, the United Kingdom, and the Ukraine—should be taken into account in deciding on appropriate policy.
To clarify the claim, assume that the world consists of only two nations, one with two billion people and one with one million people. Suppose that the two nations have the same aggregate emissions rate. Would it make sense to say that the two should be allocated the same level of emissions rights, for purposes of a system of cap and trade? Intuition suggests not, and therefore China argues that all citizens should have a right to the same level of opportunity, which means that emissions rights should be allocated on a per capita basis.15
A LITTLE DOUBLESPEAK? OF “COMMON BUT DIFFERENTIATED RESPONSIBILITIES”
China’s argument for taking account of per capita emissions is captured by its support for and understanding of the principle of “common but differentiated responsibilities,”16 which has played a large role in international debates. On the surface, this principle means that a country’s obligations on climate issues should be determined by two factors: its responsibility for climate change and its capacity to cut emissions. Beneath the surface, the principle means that developed nations have to spend a great deal to reduce their emissions, while developing nations do not.
Invoking this principle, Chinese officials have called on developed countries to take the lead in cutting their emissions, and have argued that developing countries such as China are bound merely to take account of environmental issues as they continue to insure that their economies grow.17 While China’s position is not static and may be evolving, its officials have insisted that raising their citizens’ standard of living is their first priority.18 With this point in mind, the country has emphasized that any actions it takes in regard to climate change will be “within its capability based on its actual situation.”19
China also maintains that developed countries have an obligation to assist the developing world with the challenges of climate change, both through technology transfer to allow sustainable development and through financial assistance for adapting to the effects of climate change.20 This moral obligation, China argues, arises because the developed world bears the greatest share of responsibility for climate change.21 Developed countries should now use their wealth to help poor countries develop in a world where warmer climates are a serious threat.22
A CRUEL IRONY
Some of these arguments have considerable intuitive appeal. But to the extent that China claims that emissions rights should be allocated on a per capita basis, it is asking for massive redistribution from the developed nations—above all the United States—to the developing nations (most of all, to China). It is most puzzling to suggest that the redistribution should occur in the context of climate change policy.
To see the point, we need to distinguish between greenhouse gas taxes and a cap-and-trade program. Some people favor the latter. A large challenge for such programs is to decide on the initial allocation of entitlements. An obvious possibility would be to say that all of the major emitters must reduce their emissions by a stated amount, relative to what they emitted on a specified date—by, say, 3 percent relative to 2005. Analytically, this approach would be similar to a tax in terms of its distributional consequences: both take existing emissions rates as the starting point. An alternative possibility, based on per capita rates and obviously attractive to China, would be to say that each nation has a right to emit a specified amount per person. Using this approach, the United States (with over 300 million people) would have less than 30 percent of the emissions rights of either India or China (each of which has over 1 billion people). The key point is that such an approach would represent a massive transfer of resources from the United States to other nations. Indeed, the transfer would be worth hundreds of billions of dollars.
Suppose that total global emissions were capped at their 2005 levels, and that emissions rights were allocated on a per capita basis. For the United States, such an approach would require American companies to purchase hundreds of billions of dollars in emissions rights from China and other nations. But there is no sign that the United States intends to give hundreds of billions of dollars to China or India. Any proposal that it should do so, in general or in the context of climate change, would be widely unpopular, to say the least, and domestic political constraints would doom any such proposal. And if the United States does decide to give hundreds of billions of dollars to poor nations, why should the gift take the form of emissions rights?
It is increasingly clear that an international agreement to control climate change is necessary to reduce the risk of serious and potentially catastrophic harm. If the United States agrees to participate in a climate change agreement on terms that help the world, there would be no reason to object. Compared with continued inaction, participation under those terms would be honorable. The cruel irony is that weak arguments from distributive and corrective justice, designed to promote participation by the United States and other wealthy nations, appear to be creating an obstacle to a sensible agreement—and are thus serving to harm poor nations most of all.