This book makes an important contribution to a growing body of literature that turns to history in order to derive insights into present-day dilemmas about intervention, and particularly intervention aimed at protecting vulnerable people from atrocities. Michael Doyle, who has written several influential works exploring the usefulness of particular historical ideas and practices for today’s world, takes as his starting point J. S. Mill’s classic 1859 essay, “A Few Words on Non-Intervention,” which, he says, is “the genuine locus classicus of the modern debate” (p. xi).

Doyle follows Mill in arguing that our judgments about whether or not to intervene, and how an intervention should be conducted, should be guided in large part by consideration of the consequences. What matters most is whether the proposed intervention will do more good than harm. However, he contests Mill’s conclusions at several points and seeks to outline what he thinks are better standards for deciding on matters of intervention. He tends to challenge Mill on the grounds that his interpretation of particular historical examples was flawed or that the particular problems that we are confronted with today require different solutions, not that his ethical reasoning was problematic.

A key contribution that Mill made in his essay, Doyle claims, was to suggest practical ways to balance three contradictory principles: the cosmopolitan commitment to protect basic human dignity and welfare, the communitarian commitment to respect national self-determination, and the necessity of ensuring national security. These three principles are each morally valuable, and we need to take account of them when thinking through questions of intervention, Doyle says. He begins to do so by elucidating the reasons for valuing the principle of nonintervention (Chapter 1). This includes a fascinating analysis of the low success rates and counterproductive effects of various kinds of interventions over the last two centuries. Nevertheless, drawing on Mill, he then explains how it is sometimes justifiable to “override” this principle of nonintervention for reasons of national security or to protect fellow humans against mass atrocities (Chapter 2), and also how it can be justifiable to “disregard” the principle when the idea of self-determination underpinning it no longer fits the case, either in cases of legitimate secession or illegitimate foreign intervention (Chapter 3).

Then in Chapter 4, Doyle offers a cautious defense of the “Responsibility to Protect” (RtoP) concept that has emerged in recent years, which, he suggests, provides a useful “substantive license” for interventions that are necessary for the prevention of mass atrocities but also a valuable “procedural leash” on states that would seek to undertake unilateral and abusive interventions (p. 139). This chapter features a particularly insightful analysis of the 2011 Libyan intervention and the difficulties of postconflict insecurity and chaos that now confront the Libyan people, but it also repeatedly features what I think is a problematic claim that the RtoP concept somehow contradicts established international law on the use of force. The fifth and final chapter explores the ethics of postbellum peacebuilding, considering the rights and duties of both the interveners and the intervened.

One aspect of the author’s argument that I suspect will trouble some readers is his treatment of Mill’s infamous, though fairly conventional, justification for benign intervention and imperial rule over non-European peoples. Doyle concedes that Mill’s argument is “problematic” and “Orientalist.” However, rather than engaging closely with these ethical concerns, he simply claims that “Mill’s argument for trusteeship begins to address one serious gap in strategies of humanitarian assistance,” which is the question of how to help failed states that require postbellum rebuilding (p. 107). The “modern answer,” he says, is “multilateral peacebuilding,” which is “an occupation that is designed to promote human rights and local self-determination” and which avoids the dangers of imperialism. Doyle makes surprisingly little effort to grapple with the prejudices underpinning Mill’s suggestion that non-European peoples should be subject to different rules of intervention and occupation than Europeans. Nor does he wrestle with the argument made by numerous scholars that similar or different prejudices might be at play in practices of intervention and postbellum peacebuilding today.

One other minor quibble: While it is usually poor form to critique an author for choosing to write about one thing rather than another, I tend to think that with much of The Question of Intervention focused on RtoP, Doyle missed an important opportunity to say something about the idea at the heart of RtoP; that the states comprising the international community should understand that they have not merely a discretionary right to work collectively to protect populations but also a responsibility to do so. While this is an issue that has exercised the minds of other students of Mill, such as Michael Walzer, Doyle declares at the outset that he will “focus on when intervention is permissible, not necessarily when it is desirable from the point of view of the intervener” (p. 6). The need to move beyond debates about the permissibility or right of humanitarian intervention and to encourage states to reinterpret their conception of what is desirable and to generate the political will to save strangers was precisely what motivated the development of the concept of the RtoP. The case study used by Doyle to explore the question of the permissibility of humanitarian intervention is the 1994 Rwandan genocide. But, as many commentators have noted, the failure of the international community to prevent or stop this genocide was produced not by concerns over whether there existed a right to intervene so much as by an unwillingness of states to take up the burden of responsibility to do so. As important as the question of permissibility is, an answer in favor of intervention provides little succor to victims of atrocities if no states are willing to act.

Those quibbles aside, this book makes an impressive contribution to the ongoing debate about the ethics of intervention. Doyle has yet again provided us with a valuable model for ways in which to carefully draw on the ideas of past thinkers and apply them to our own problems today, and his conclusions deserve a wide audience.