Climate justice is an idea more often proclaimed than subject to rigorous philosophical analysis. Henry Shue’s book succeeds in remedying this shortcoming. It provides an invaluable guide to countering commonplace arguments on the avoidance of national and individual responsibility for dealing with climate change or, most significantly, that such action can be delayed, shirked, or left to those technologies that may become available to future generations. While there are manifold self-interested arguments for addressing the climate emergency, the contribution of this study is to lay out the moral reasoning for action. The fundamental message, conveyed in the book’s title, is that such action must be taken by citizens who are alive now—“the pivotal generation.”

Shue’s argument proceeds from an underlying assumption of the unity of humankind and the “deep continuity” that exists between past, present, and future generations. Its other foundation is in an up-to-date appreciation of climate science. Thus he does not argue, as some commentators do, that human extinction is just around the corner, but that we face a whole range of potentially limitless and threatening possibilities some of which we have made inevitable, for example the collapse of the West Antarctic Ice Sheet. Others may still be avoided if we manage to “stop feeding climate change.” The present generation has a unique obligation to posterity because it is in a position to understand the trends and consequences of climate change that will impose much greater and potentially unlimited dangers and catastrophic “tipping points” on those who will succeed it. “If any human duty is unconditional, it is the duty to preserve the fundamental conditions, including the physical preconditions of human society, by avoiding dangerous threats to those conditions” (pp. 17–18). Responsibility for cumulative greenhouse gas emissions, in what Shue terms “sovereign externalization,” cannot be avoided by developed nations whose citizens have reaped the benefits of industrialization. The claims of the Trump administration that the United States had no obligation to the Paris Agreement, or for the redistribution of wealth, are effectively demolished both in terms of pure fairness and the wrongful imposition of costs.

The third chapter of the book provides a fascinating analysis of responsibility and agency across distance and time, which confirms that contemporary citizens cannot deny engagement with previous and succeeding generations in relation to the climate crisis. This is given particular point by scientific awareness that we are at the “date of last opportunity to prevent disaster” (p. 77). Such urgency is often obscured or denied in contemporary political discourse, which tends to resolve concerns about a rapidly deteriorating climate by postponing radical action in the hope that future technologies in geo-engineering and carbon dioxide removal will ride to the rescue of humanity. Here, again, Shue effectively undermines not only the feasibility but also the morality of a belief that there will be a “second chance” to deal with climate change.

Over the last 30 years in which, as he notes, we have pumped almost as much greenhouse gas into the atmosphere as all preceding generations (p. 91), the author has contributed prominently to the philosophical underpinnings of an increasingly urgent climate debate. One of the virtues of this book is that it brings together, in an accessible form, a number of his key contributions on the unavoidability of justice, the difference between “subsistence” and “luxury” emissions and “climate dreaming.” For those who would wish to enquire further into Shue’s own work and that of other writers in the field there are 30 pages of detailed endnotes and a brief appendix on the meaning of inequality.

The book is primarily and self-consciously aimed at the American public. Although it deals in general terms with the moral impossibility of denying the right to develop to counties (like India and China) whose rising emissions are only the proverbial straw that will break the climate stability camel’s back, it does not address in any detail current North–South justice arguments about adaptation and “loss and damage.” The justice claims of small island states, threatened with extinction, and debt-ridden African nations whose budgets are already being undermined by the effects of actual climate change, continue to be denied by the developed world. The United States and European Union have firmly refused to accept any liability for “loss and damage” to developing countries and the resulting dispute threatens the future of the Paris Agreement.

In a justifiably angry final chapter on the political implications of the preceding argument, Shue takes aim at a corrupt power structure that has embedded the interests of fossil fuel producers to the extent that global energy subsidies exceed world public expenditure on health (p. 123). Major energy corporations have moved from a position of climate denial to a range of obfuscatory and “greenwashing” tactics that serve to fatally postpone the achievement of the Paris Agreement targets.

The least developed and final part of the book addresses the key question of what members of the pivotal generation, convinced by the powerful moral argument in the preceding chapters, might be able to do. Shue makes some suggestions of how the “many” can confront “the ruthless few” through consumer choice, disinvestment in banks that continue to finance fossil fuels and both local and national political activism where “Every election now needs to be about climate change” (p. 131). He also expresses the “need to build social movements to attack directly the economic and political structures that with all their influence and guile are blocking comprehensive measures to reduce carbon emissions” (p. 119). Such movements already exist and Extinction Rebellion in Europe has demonstrated the illegal and disruptive lengths to which citizens, convinced of the urgency of the situation are prepared to go. This raises crucial, but unanswered, questions about the extent to which the unique situation of the pivotal generation can justify extreme forms of direct action.

To conclude, the case that those of us now alive confront a critical and unique historical opportunity is well made in this book. Most impressive is the depth and philosophical precision of the arguments that Shue constructs concerning moral responsibility and agency. Anyone involved in academic or political debate about the escalating climate emergency would benefit from reading this work. However, the complexity and sophistication of much of the argumentation may struggle to get a hearing among the polarized simplicities of contemporary American (and other developed world) politics.