This chapter introduces the commitment problem. In some cases, states may recognize the existence of mutually preferable settlements. However, one or both may be unable to credibly commit to the conditions necessary to implement those settlements. As a result, the states fight. In particular, this chapter’s focus is on how power dynamics can create such commitment problems.

It is a sad and depressing reality that, for any international lawyer interested and working in the field of international law governing the use of military force by and between states (the ‘jus ad bellum’), business tends to be bad during moments of relative peace and stability. Arguably even more depressing, however, is the fact that this is not often the case.

Previous chapters treated war as a game-ending decision. In practice, negotiations may continue even if the first round of bargaining fails. This chapter covers three different versions of the problem. First, we see that states can learn directly from who wins or loses on the battlefield. Second, states can implicitly learn based on the differential costs of war two types pay. Finally, against multiple bargaining opponents, accepting small proposals can signal weakness for future negotiations. Rather than always lead to more war, it is possible that this instead causes the first proposers to be more generous. Overall, we see that these models are substantially more difficult to work with because of the manipulation of beliefs throughout the rounds of negotiations.

When most of us hear the word “politics” we think of either fights between political parties, fractious policy debates, or a manipulative and self-interested form of negotiation expressed in the phrase “they’re playing politics with the issue.” But underneath the polarization, rage tweets, and backroom deals is the reality that politics is the description of a moral and existential good. Politics embodies the recognition that some kind of common life with others must be cultivated and sustained over time if life is to go on.

Intimacy is a basic building block of a flourishing life. A lack of intimacy and the resulting loneliness and sense of isolation can cause dire physical, mental, and public health problems that in turn diminish our ability to act with and for others.1 This chapter begins by focusing on intimacy in general, which then frames a more specific focus on sexual intimacy and the intimacies of home. My argument is that vulnerability is an inherent feature of creatureliness that can be metabolized in ways that produce either intimacy or precarity. On my account, intimacy is a moral relation that specifies what love and justice mean in practice.

What is generally true about all models of crisis bargaining? Answering a question like this seems daunting because there are infinitely many ways states could negotiate with one another. Fortunately, this chapter introduces a new tool to address the question: mechanism design. We see that types with higher war payoffs will always fight more often than types with lower payoffs, and they will receive better payoffs overall. Meanwhile, it is possible to have negotiations end with guaranteed peace under uncertainty over costs, but no such solution may be possible with uncertainty over power.

When my family and I moved to the United States, my eldest son had never played or seen a game of basketball. He was not even that interested in sports. But on arrival, he was invited to join a neighborhood recreational team. That opportunity awakened a love for the game that then became his passion until he went to university. As it turned out, being a serious basketball player in North Carolina is not a trivial matter. It structured much of his life, including how he experienced school, our town, the intersections of gender, class, and race, as well as his own physical development. However, there was neither an identity nor a way of acting as a basketball player that was somehow hidden inside him waiting to jump out.

Sojourner Truth was an abolitionist and women’s rights activist who combined her own experience of slavery, empirical evidence about slavery, and a fervent theological vision to summon others to change. As she put it: “The Lord has made me a sign unto this nation, an’ I go round a-testifyin’, an’ showin’ on ’em their sins agin my people.”1 Sojourner Truth prophetically revealed what was going on as a prelude to demanding that those who heard her change how they lived and then join with her to abolish the system of slavery. She was a witness.

Chapter 5 has as its focus not the institution of peacekeeping per se, but more specifically the use of force within, and as a now an integral part of, United Nations peacekeeping. It begins by attempting to define UN peacekeeping, given its absence from the UN Charter, and goes on to address the legal basis for peacekeeping operations and the basic principles of peacekeeping. The chapter then traces the development of peacekeeping, from the early UN Charter-era operations, which saw the establishment of the basic principles, through to the challenges to these principles, which did not take long to manifest themselves, in particular through the use of forcible measures by peacekeeping forces. Finally, the chapter examines the evolution of the use of force within peacekeeping missions, from simple self-defence to the implementation and enforcement of robust mandates, and assesses not only whether the various forms of forcible peacekeeping can be reconciled with the fundamental principles of peacekeeping, but also whether peacekeeping has now taken on a war-fighting role.

This chapter explores the second main source of uncertainty in crisis bargaining: power. At first, the results appear to be superficially similar to how uncertainty over costs works. However, upon deeper inspection, uncertainty over power is harder to mitigate. Even a clever mediator might struggle to solve the problem. Further, states have an incentive to strategically create such uncertainty for their opponents because free riding by not constructing weapons is a tempting choice.

This appendix provides a brief overview of how to calculate and manipulate infinite streams of payoffs.

I remember vividly seeing footage on the news of the space shuttle Challenger launching on January 28, 1986. Seventy-four seconds after takeoff it exploded, killing all seven crew members. The immediate cause of the explosion was a technical fault. But it was not just a mechanical failure that led to the deaths of everyone on board. The cause was also a failure of character. The Challenger space shuttle disaster was investigated by a presidential commission and subsequently the subject of extensive research and analysis.

On August 26, 1572, Peter Ramus was stabbed to death in his study, his body thrown out the window, mutilated, and then cast into the Seine. He was one of thousands killed over a period of a few days in Paris and then over several weeks as the violence spread beyond the city. This bloodletting came to be known as the St. Bartholomew’s Day Massacre. The reason for the massacre was ostensibly a conflict between Catholics and Protestants. But it also had to do with court intrigue, mob violence, the settling of scores, and a sporadic civil war that had begun a decade earlier.

To be a moral person is always a struggle. Converting one’s temptations into virtue and foolishness into wisdom is a part of the struggle, as is transforming places and peoples accursed by abuse and injustice into a realm of blessing. But we cannot do either alone. Nor should we. The gift of coming together with others in a shared struggle to live well is that, in doing so, we discover who we are already in Christ and forge more loving and just forms of common life that anticipate and witness to the world as it will be in Christ.

Chapter 10 focuses on the somewhat controversial doctrine of humanitarian intervention. It assesses the issue of whether the doctrine can be reconciled with the UN Charter, before examining state practice in connection with the doctrine, including taking a look at Cold War and post-Cold War practice in assessing the position of the doctrine during the UN era. Given that the forcible entry by the North Atlantic Treaty Organization in the Kosovo crisis in 1999 proved something of a landmark in terms of events that have shaped the path of the modern doctrine, the status of the doctrine in the immediate aftermath of this intervention is given particular attention, as well as the impact that the war in Ukraine has had and whether there is an obligation to intervene in the context of genocides. The chapter then looks at the Syrian civil war and the relevance of the doctrine of humanitarian intervention to that particularly tragic conflict, which continues at the time of writing. A conception of the doctrine that has come to dominate contemporary debates is that of the ‘Responsibility to Protect’. Given its relatively recent rise to prominence, its impact upon the doctrine of humanitarian intervention is assessed.