This chapter begins by discussing how the crime of aggression differs from all other core international crimes in being inextricably linked to an act of aggression by a state against another state. It then turns to a discussion of the history of the crime of aggression, including its inclusion in the Statute of the International Criminal Court (ICC). It covers the definition of the crime of aggression as set out in Article 8bis of the ICC Statute, as well as its relationship with other crimes. It also examines the material elements: (1) by a perpetrator in a leadership position in a state (2) who has participated (3) in an act of aggression by the state (4) which ‘by its character, gravity and scale, constitutes a manifest violation of the Charter of the United Nations’. It also explains the mental elements as set out in Elements 4 and 6 of the ICC’s Elements of Crime; the jurisdiction of the ICC over aggression, including the role of the Security Council; and the implications of an ICC prosecution of the crime of aggression.

While the focus of the book is on the interstate use of force post-WWII, this chapter holds a rear mirror and offers a perspective of evolution of restraints that started long before states came into being. It recounts how human societies over the centuries became states free from widespread internal use of armed force and how great powers sought to avoid major armed conflicts through policies of balance of power and multilateral conferences. It describes how they developed common rules by concluding conventions and built institutions such as the League of Nations and the United Nations to create a rule-based order and mechanisms and methods to prevent the interstate use of force.

Anti-satellite weapons that rely on violent impacts and create space debris are regarded as a major threat to the exploration and use of space, including the use of space assets for communications and Earth imaging. This chapter examines two ways in which the testing of such ‘kinetic’ weapons might already have become illegal. First, the accepted interpretation of Article I of the Outer Space Treaty may be evolving as a result of the changing practice of the parties to that treaty. In short, many states are behaving as if tests of anti-satellite weapons that create debris are contrary to the ‘freedom of exploration and use of space’. Second, the same practice and an accompanying opinio juris may be contributing to the development of a parallel rule of customary international law. This chapter also examines the legality of the use of kinetic anti-satellite weapons, as opposed to their testing. Two additional, separate bodies of international law are relevant here: the jus ad bellum governing the recourse to armed force, which includes the right of self-defence, and the jus in bello governing the conduct of armed conflict. A close analysis leads to the conclusion that any use of a kinetic anti-satellite weapon would be illegal today because of the growing crisis of space debris.

A power on the part of the General Assembly of the United Nations to decide on a partition of Palestine was said to flow from the text of the Charter of the United Nations. The Charter, however, gives the General Assembly decision-making powers only with respect to issues internal to the United Nations. It was argued that the member states construed the Charter so as to give it a power to partition Palestine. In response, it was argued that the member states did not do so. Many of them wanted the International Court of Justice to decide that point. It was argued that even if the Charter did not explicitly give a power to partition Palestine, such a power was implied by the Charter. In response, it was argued that there was no basis for such an implication.

We present an overview of the evolution of the United Nations General Assembly, its most important achievements and remaining weaknesses and relevance. It is argued that the UN Charter should be amended to introduce a system of weighted voting, to better reflect the relative significance and influence of its 193 members. A proposal is put forward that uses three variables to arrive at a set of weights for membership in the General Assembly: (i) population size, to reflect each member’s accumulated demographic history so that countries with larger populations will have a larger voice; (ii) the size of the member’s economy; and (iii) a UN membership factor that is equal for all countries. For the GDP variable, the weighted average of GDP at market prices and GDP at PPP rates is used. The merits and limitations of such a scheme are analyzed and a gradual system of direct election of Assembly members is proposed. The chapter also presents the UN Charter’s Articles 9–11 on General Assembly composition, functions and powers and discusses how these Articles should be amended to reflect the new system of weighted voting and the enhanced powers that are envisaged for the Assembly under a revised Charter.

Within the normative framework of the Universal Declaration and the International Covenants on human rights the chapter lays out the principal arguments for and against a right to enter a country and settle with the exception of persons who constitute a threat to public health, safety, morality, or national security. The author demonstrates, for instance, that freedom of association can be invoked by both supporters of open borders and supporters of a sovereign right to determine who may enter and on what conditions. He notes, however, that a state has special moral obligations to potential migrants from countries whose toxic conditions driving migration are at least partially attributable to past behavior by the receiving state in that country’s territory. Colonial exploitation would be an example. Refugees, persons fleeing persecution or natural disasters or armed conflicts, the author argues, have a particularly powerful moral claim to enter and an indisputable claim under international law. However, just how far the moral claim extends is not entirely clear. The chapter concludes by examining and endorsing the proposal of Betts and Collier to convert refugee camps outside the West into real communities.