The essays in this volume have presented a myriad of viewpoints on complex moral, legal, and political topics at the end of war. Retribution, reconciliation, truth telling, and reparations are all aimed at peace building in a society that has been recently ravaged by war or atrocities. These topics are as old as civilizations themselves. But they have recently been discussed under the labels of jus post bellum and “transitional justice.” How different such considerations are today compared with centuries or millennia ago is unclear. Nonetheless the essays have attempted to provide fresh considerations of both conceptual and practical significance. The authors have not all agreed with each other, even as they have seen themselves as all pursuing the similar topic of peace building.

As we have seen, the two concluding essays in this volume call into question the very notion of jus post bellum. Since we have already briefly summarized the arguments in the introduction, we will use the conclusion as an opportunity to show how the other arguments may offer responses to these challenges, even as the worries expressed in the last two essays will surely remain a major challenge to jus post bellum theorizing. Jus Post Bellum remains a somewhat controversial new area of scholarship. To be sure, as we have seen throughout this volume, central jus post bellum principles such as retribution, reparations, and reconciliation continue to be debated extensively in legal and moral literatures.

Let us first start with the idea of jus post bellum and its relationship to transitional justice. Jus post bellum is certainly not yet a distinct field of inquiry, nor is it a recognized body of moral or legal norms. At the moment, jus post bellum is a set of topics and concepts that all relate, in various ways, to the situation that exists at the end of a war or armed conflict. Transitional justice is also not yet established as a field of inquiry or a definite set of norms. At the moment transitional justice is a set of topics and concepts that relate to the period between mass atrocity and return to the rule of law, and possibly a democratic order. In this sense, both jus post bellum and transitional justice concern justice issues at the end of mass upheaval either because of war or atrocity. This is not a clearly distinct period but it is a situation where norms are in flux and where it is unclear what is to be done so that justice can be attained.

As we said in the introductory chapter, jus post bellum is a term meant to be a complement to jus ad bellum and jus in bello. So how one views jus post bellum will be determined partially by how one views these other two domains. Some who work in international law have used these terms to refer to the bodies of law that concern aggression and war crimes respectively. So some international lawyers have been justifiably worried that talk of jus post bellum translates into talk about a new regime of international law. The worry is that (1) such a regime is probably not needed given the norms already in place, and (2) such a regime can not merely be established by even well-intentioned theorists but must achieve legitimacy by either multilateral contract or longstanding custom. Those who work in just war theory have similarly been concerned that a new regime of moral norms might be proposed to supplant or at least compete with well established moral norms concerning aggression on the one hand and the rules of war on the other, again corresponding to the well-trod accounts of jus ad bellum and jus in bello in moral philosophy.

These worries about the scope and even the point of discussing jus post bellum are sincere and important, in our view. One of us, Larry May, has just written a volume setting out a framework for thinking of jus post bellum, but is mindful of these worries throughout his text.¹ One can treat the subjects of jus post bellum as separate topics, such as reconciliation, retribution, or reparations. But to do so fails to see that these topics are intimately related to each other. Retribution can conflict with reconciliation, as has been seen most dramatically by the indictment by the ICC of President Al Bashir of the Sudan, where the very unsealing of the indictment caused the human rights atrocities to increase and the likelihood of reconciliation to decrease at a crucial stage in the beginnings of peace building in the Sudan.

Whether we see the various topics considered in this book as forming parts of a coherent whole or merely as topics that need to be addressed together because they can conflict with each other, jus post bellum is probably here to stay. In this respect, what are we to think of the critical essays by Cryer and Lazar? In what follows we will provide two ways to characterize their challenge: one as a structural challenge to the whole enterprise of just post bellum theorizing, and the other, perhaps more plausibly, as a set of very important cautionary notes to the emerging literature that our volume contributes to.

Let us turn to a methodological point concerning the structure of the skeptical arguments of Cryer and Lazar – arguments that call into question the theoretical or practical usefulness of a term such as jus post bellum. Successful versions of such arguments typically involve two steps. The first step is pinning down or defining the term in question. The second step involves demonstrating how the term as it is defined in step one, if the argument is theoretical, is covered by other existing terms or categories. Or, if the argument is practical (or legal), the strategy is to show that the employment of the term would lead to a worse state of affairs than other competing alternatives.

We can see this two-step process employed in both of the last two essays. Lazar, when taking a more practical approach, argues that the implementation of three of the common principles of jus post bellum lead to morally problematic scenarios. Additionally, on the more theoretical side, he argues that just war theory can be conceptually complete without referring to jus post bellum; that is, that jus ad bellum and jus in bello cover all that is important about jus post bellum, making it a parasitic and unnecessary concept. Cryer, focusing on the legal and practical implications of the term, argues that it is better to keep our current legal system, which embodies jus ad bellum and jus in bello principles, than to move to the jus post bellum paradigm. Their arguments are forceful. Both demonstrate key theoretical and practical problems with jus post bellum. So let us assume that the second step of their arguments is successful.

Yet it is often the first step in this process that is the most difficult, since, as this volume illustrates, there are a multitude of conceptions of the same concept. Here we draw on a common distinction between a concept and a conception. We can explain this distinction in the following way: The “concept” of jus post bellum introduces the problem, perhaps as general as: “What does justice look like after war?” The “conceptions” of jus post bellum are the various solutions proposed to address this question. The problem is that various philosophers provide different and sometimes incompatible conceptions of the “concept” of jus post bellum. As we attempted to show in the introductory chapter, many of the theses – for example, of Clark, Coady, Drumbl, Kyriakakis, and May, to name a few obvious cases – reject at least some key features of the current conceptions of jus post bellum.

There is an additional burden placed on skepticism toward a concept generally, as opposed to arguments that merely wish to revise or refine a particular conception, since it must be shown that the properties that are rejected are properties necessary for any conception of the concept. Call this the broad skeptical argument. This as opposed to what we might call a narrow skeptical argument, which is in many respects no different than the arguments offered by Clark, Coady, Drumbl, Kyriakakis, May, and others. That is, it is an argument that attempts to demonstrate a flaw with a particular (typically the most prominent) conception of jus post bellum. (To be clear, the arguments of this list of authors are employed typically as a way of setting up a positive proposal. Their arguments are, in most cases, not solely skeptical arguments.) The question thus becomes which version of the skeptical argument – broad or narrow – does Lazar or Cryer offer?

Lazar and Cryer are well aware of the burden described above. Indeed, Cryer devotes a section – “What is the Jus Post Bellum” – to the problematic nature of the term and ultimately qualifies his critique, stating, “this critique is not intended as a refutation of all possible uses of the term but is limited to the idea that the jus post bellum ought to be conceptualised as a matter of law in which some of its most vocal supporters have suggested.”² Cryer’s argument, seemingly a narrow skeptical argument, does not call for a rejection of the project of detailing a jus post bellum.

Lazar’s skepticism is a bit more complicated, for he offers two different arguments against jus post bellum. He first tries to show the incompatibility of three principles of jus post bellum – that compensation should be a priority; that punishment of political leaders and war criminals even in the absence of legitimate multilateral institutions should be a priority; and that when states justifiably launch armed humanitarian interventions, they become responsible for reconstructing the states into which they have intervened. If this were to be a broad skeptical argument, Lazar would need to show that the three properties that he criticizes are properties necessary to all conceptions of jus post bellum. Wisely, Lazar does not attempt to hold this position; instead, he claims that these are commonly reaffirmed positions, but that they are not well understood as conflicting. So we can safely say that the first of Lazar’s arguments is only narrowly skeptical.

Lazar’s second argument, however, takes a broader approach. He holds that on the most generous interpretation, “jus post bellum governs the practice of war fighting ex post”³ and as a result,“ad bellum, in bello, and ex bello standards determine both the grounds and the content of our post bellum duties. Our responsibilities after war are grounded in our having met or breached those ad bellum, in bello, and ex bello standards.”⁴ If this is the case, then Cryer is right to say the best interpretation of jus post bellum is “relentlessly backward-looking” and just war theory is “conceptually complete” without it. And accordingly, even the most convincing account of jus post bellum is not so convincing. Here we can see an attempt to meet the additional burden of the broad skeptical argument: Even on the most charitable interpretations, jus post bellum remains a “profoundly impoverished” concept.⁵ It theoretically adds nothing, and its implementation leads to a worse state of affairs.

Both the narrow and broad arguments offered in these essays are instructive. In what follows we will examine the areas of jus post bellum that Cryer and Lazar challenge in an attempt to answer the following questions. First, are the criticized jus post bellum principles ubiquitous among the various conceptions of jus post bellum? Second, turning to Lazar’s broad skeptical argument, if transitional justice is included as part of jus post bellum, is Lazar’s criticism compatible with a particular notion of jus post bellum? Taken together, a consideration of these questions highlights the key points of debate within jus post bellum theorizing, and underscores where future discussions and research need to take place.

The question of compensation seems central to jus post bellum thinking. Walker, for instance, singles it out as one of the primary points that distinguishes the transitional justice and jus post bellum frameworks. Additionally, both Clark and Davidovic discuss the unique role that compensation plays in punishment after war for Ugandans and East Timorese, respectively. In all these cases, there is serious discussion about how current jus post bellum practices could be changed for the better. And so the very terms of jus post bellum are changing as the debate continues.

May, who also advocates for changes in how to understand jus post bellum, provides an argument that runs closely parallel to the one offered by Lazar. Both hold that compensation, ideally, is something worth pursuing. But both also conclude that in real-world situations compensation should not jeopardize those in need. As Lazar puts it, “If we make compensation our guiding principle, instead of vulnerability, then we will inevitably direct resources away from those who are neediest.”⁶ May agrees with this sentiment, but this does not lead him to skepticism concerning jus post bellum; rather he argues for a modified conception of jus post bellum that allows for compensation by those who are best in a position to do so, and not necessarily by those who committed the wrong.

Let us take a specific example to reinforce the similarity between Lazar and May’s positions. Lazar, citing the sheer number of wrongful deaths that occur during war, argues that compensation would be overwhelming for a defeated unjust belligerent. And, he continues, any attempt to force the unjust belligerent to pay, would, in most cases, redirect additional resources away from the least well off. If correct, this argument calls into question the role that compensation plays in jus post bellum theorizing. However, insofar as one adopts a conception of jus post bellum similar to the one endorsed by May – that those wronged should sometimes demand less than their due, and that compensation should not necessarily be paid by the wrongdoer but by the one who is in a position to do so – it seems that one can be sympathetic to Lazar’s worries without abandoning jus post bellum altogether.

This discussion illustrates that insofar as May offers a viable alternative, it seems we can allay many of Lazar’s worries concerning compensation. Now, the question is: Does May offer a workable alternative? Lazar argues that consistency demands the negative implications of compensation that he enumerates in his essay, so perhaps it could be argued that there are inconsistencies in May’s (and similar) accounts. Specifically, it could be argued that May is working within the transitional justice paradigm, and hence it could be argued that this entire paradigm is inconsistent with jus post bellum. (We will return to the relationship between transitional justice and jus post bellum.)

The same sort of question can be asked of Lazar and Cryer’s claims that the punishment of war criminals under the current jus post bellum rubric produces various wrongs. Again, some of the other authors offer similar critiques of current jus post bellum theories and practices, but these are offered as modifications or rejections of a particular conception and not rejection of the concept of jus post bellum. Davidovic elaborately describes the failings that occurred in the implementation of jus post bellum ideals in trials following the atrocities in East Timor. Kyriakakis and Drumbl, wanting to expand the current system, articulate the injustices that occur when economic actors and child soldiers are overlooked. And Clark shows that the injustices involved in the current concentration on punishing elites is unacceptable and that community-based practices might be better able to accommodate a wider scope of punishment. Each of these views clashes with some prominent conception of jus post bellum, and each tends to be compatible with the narrower skeptical versions of Lazar and Cryer’s critiques.

Here we should note that Cryer might argue that the different conceptions of jus post bellum just canvassed only strengthens his point that legal institutions should not employ a system that has yet to be worked out, since it would invite abuse. This is an important point. In any move from what seems to be a good idea in theory to putting it into practice one must worry that other practical proposals might conflict with the implementation of any other unless there is a somewhat unified approach where one thinks about all of the parts of a jus post bellum taken together.

In the small sample of the arguments that we have revisited here there emerges an underlying question as to what should be the primary focus of jus post bellum. On the one hand, as Lazar rightly points out in his broad skeptical argument, jus post bellum seems to be severely backward looking. For example, the upshot of Coady’s argument is that the treatment of troops after the war ends needs to be in line with the jus ad bello and jus in bello considerations. On the other hand, there is a strong push to merge transitional justice with jus post bellum, which shifts the perspective forward. On this second view, the goal of jus post bellum is a just and lasting peace. And this might even mean, as Talisse has argued, a lasting peace under a stable democracy. In this respect, much of what Lazar argues for could be readily accepted by transitional justice theorists. For instance, Lazar concludes his essay with a statement that could have just as easily come from Walker’s or May’s piece, as well as nearly everyone else in the volume, that: “Instead of confining ourselves to the ex post enforcement of just war principles, we should develop an ethics of peacebuilding.”⁷

So, if one is sympathetic to the skeptical arguments of the essays by Cryer and Lazar about the nature of jus post bellum, perhaps one can simply read, or re-read, the essays in the volume as centering on the ethics of peace building. However one views the essays in this collection, we believe that the debates on the topics such as retribution, reparations, and reconciliation will nonetheless be significantly advanced. What we have offered is a set of new essays on topics that are at the cutting edge of theorizing about the situation after war or atrocity has ended. All of the essays work to this end, even those that remain skeptical about whether there is a distinct field of inquiry, or a unique set of moral or legal norms, that can be properly called jus post bellum.

War and mass atrocity have historically created special problems for the future peace of societies affected by them. The case studies of East Timor, Rwanda, and the Congo illustrate this in especially poignant and terrible ways. Yet the essays in this book are filled with hope. We can live through tragedy and still find the resources to rebuild and to live in harmony with each other again. The emerging area of scholarship on jus post bellum contributes to the understanding and practical resolution of the immense problems that confront societies at the end of war or mass atrocity. Peace building is difficult in such situations but not impossible.