14. Enforcement

This chapter analyses the enforcement of international law by States acting individually, that is, decentralized enforcement, including by their courts, as well as through retortion or countermeasures (once called reprisals). This is the typical form of enforcement under traditional international law. At the same time, enforcement might take place through measures taken by States acting collectively, that is, through mechanisms that include resort to collective measures, such as those adopted at the UN level (or within other international organizations), which can lead to collective sanctions. The first form of enforcement looks at the traditional law governing retortion and reprisals or countermeasures (as they are now called), as well as at the post-1945 law, taking into account that the ban on the use of armed force in international relations imposes that all enforcement measures taken by States individually must be peaceful. The second form examines the issue of collective sanctions, such as those taken at UN level.

13. Peaceful Settlement of International Disputes

The general obligation of peaceful settlement of disputes complementing the general ban on the use or threat of force prompted States to revitalize and strengthen the traditional means for settling disputes and establish innovative and flexible mechanisms for preventing disputes or, more generally, inducing compliance with international law. This chapter discusses the so-called diplomatic mechanisms for promoting agreement between disputants, the so-called judicial means (arbitration and adjudication), and the interplay between them. The chapter further examines the establishment of more flexible mechanisms for either preventing or settling disputes, in particular non-compliance and supervisory procedures.

9. Law-Making Processes

Custom and treaties constitute the two most important formal sources of international law, that are also envisaged in Article 38 of the ICJ Statute. In addition, Article 38 refers to general principles of law recognized in domestic systems. This chapter examines these three formal sources of international law as well as some others, in particular unilateral acts of States and binding decisions of international organizations. In addition, it discusses equity and soft law and examines some mechanisms of identification and development of international law, such as jurisprudence, doctrine, and codification.

3. The Fundamental Principles Governing International Relations

This chapter discusses the fundamental principles governing international relations. The principles represent the fundamental set of standards on which States are united and which allow a degree of relatively smooth international dealings. They make up the apex of the whole body of international legislation. They constitute overriding legal standards that may be regarded as the constitutional principles of the international community. These principles are: the sovereign equality of States; the principle of non-intervention in internal affairs; the prohibition of the threat or use of force; peaceful settlement of international disputes; the duty to co-operate; the principle of good faith; self-determination of peoples; respect for human rights; and the prevention of significant environmental harm. The discussions then turn to the distinguishing traits of the fundamental principles and the close link between the principles and the need for their co-ordination.

15. The Role of the United Nations

This chapter discusses the role of the United Nations (UN), covering the grand design of the post-Second World War period, the ideals of the primacy of international law, the goals and structure of the new organization, the principal achievements and failures, and the current role of the UN, particularly in light of the adoption in 2015 of the UN Sustainable Development Goals (SDGs)—a new Agenda in which all UN goals tend to come together. The chapter describes the functions and roles of the principal organs of the UN and the interplay between them. It argues that since the UN came into existence it has often failed in three areas: maintenance of peace and security, disarmament, and bridging the gap between industrialized and developing countries. On the other hand, progress was made in the area of self-determination of peoples and in promoting human rights, while in the area of economic co-operation, despite some progress, much more remains to be done. However, for all its deficiencies and in spite of the lack of vision of some of its Secretaries-General, the primary failings of the UN must be traced back to the States behind it, chiefly the Great Powers.

12. International State Responsibility for Wrongful Acts

The chapter begins by discussing the history of the codification of the law of State responsibility. It then considers the current regulation of State responsibility, by distinguishing the ‘ordinary’ legal regime and the ‘aggravated’ State responsibility, and goes on to explore the main differences between the two regimes. It focuses on the elements of the internationally wrongful act, particularly on the attribution of conduct to a State and the relevance of fault and damage. In addition, it examines the circumstances which preclude wrongfulness and the consequences of the internationally wrongful act (with particular reference to the obligation to provide reparation).

8. Individuals and Other Legal Subjects

This chapter discusses the legal personality under international law of a broad range of legal subjects other than States and international organizations, particularly individuals, peoples, and national liberation movements, as well as insurgents and a few other sui generis entities (including transnational corporations and non-governmental organizations). While insurgents, like States and some of the sui generis entities (the Holy See, the Sovereign Order of Malta, or the International Committee of the Red Cross), constitute traditional subjects of international law, the other categories emerged in the aftermath of the Second World War. The chapter also tackles the issue of which international rules apply to all these diverse entities and to what extent they participate in international dealings.

2. The Historical Evolution of the International Community

This chapter traces the historical evolution of the international legal system, which is organized for analytical purposes in four major stages: from its gradual emergence (sixteenth–early seventeenth century) to the First World War; from the establishment of the League of Nations to the end of the Second World War (1919–1945); from the establishment of the United Nations to the end of the Cold War (1945–1989); and the last three decades since the end of the Cold War (1990–2020). The chapter emphasizes the European roots of international law but also the pressure it has faced since the 1960s to reflect the interests of developing and newly independent States. It also provides some basic historical elements and references to the growing literature on the history of international law, which are useful to understand the historical context of the material examined in subsequent chapters.

21. International Law and the Global Economy

This chapter discusses the historical development and contemporary operation of international economic law, with a focus on trade, development, and monetary and investment relations. It pays particular attention to the emergence of the system with the 1944 Bretton Woods Conferences establishing the IMF and the World Bank, the adoption of the GATT in 1947, the revindications and influence of developing countries on the evolution of the system (with the declaration of a New International Economic Order), and the contemporary law of international trade (under the World Trade Organization) and foreign investment transactions (under investment agreements protected by investment arbitration organized under the ICSID).

19. The Repression of International Crimes

This chapter begins with an overview of international crimes, namely, offences entailing the personal criminal liability of the individuals concerned (as opposed to the responsibility of the State) under international law. International crimes include war crimes, crimes against humanity, genocide, torture, aggression, and terrorism. The discussion then turns to the prosecution and punishment by State courts, focusing on the grounds of criminal jurisdiction and in particular universal criminal jurisdiction. It ends with an overview of the prosecution and punishment by international criminal courts and tribunals, with an emphasis on the International Criminal Court, and with an assessment of the main problems besetting international criminal proceedings.