This chapter introduces an idea that has enjoyed a remarkable, if hotly contested, development in the post-Cold War era: humanitarian intervention. Based on a commitment to principles of humanity and respect for life, such action seeks to alleviate the unnecessary suffering caused by violent conflict through intervening in another state, with force under limited conditions. The chapter outlines the origins of humanitarianism and the history of humanitarian intervention before discussing the shift to the responsibility to protect (R2P). As world politics becomes ever more complex, debate about global responsibilities to protect suffering strangers will continue to shape the theory and practice of international relations. While abuse of human beings has not become less widespread, the preoccupation with COVID-19 and domestic priorities meant that little consideration was given to robust action against middle powers perpetrating mass atrocities in such places as Myanmar and Tigray, let alone against major powers in Ukraine and Xinjiang.

This chapter examines the politics of global poverty, inequality and development. The first section provides the background for our analysis of global poverty and inequality. Any meaningful discussion of poverty and inequality necessarily has to be in relation to development – which, as we show, is itself contested in theory and practice. The second section provides an outline of a relational perspective of global development. The third section focuses on the United Nations’ 2030 Sustainable Development Goals (SDGs) agenda. We conclude with some critical observations about the political significance of the relationship between development, poverty and inequality.

This chapter gives an overview of the theory and practice of global climate politics. First, it provides a brief history of the politics of climate change as they play out in the international negotiations on the issue overseen by the United Nations . Second, it looks at the formal organisational and institutional structures that exist to manage the international community’s response to climate change. Third, it reviews the ways in which different theories of International Relations have been applied to climate change, assessing both their potential and their limitations. Finally, the conclusion offers some thoughts on the evolving nature of the ‘global’ governance of climate change.

This chapter introduces a new research program on the politics of religion and secularism. A focus on the politics of religion and secularism offers a productive port of entry into the study of international politics. Following a brief introduction to religion and international relations, it offers a basic introduction to the concept of secularism, explains why the politics of secularism is significant to the study of global politics and concludes with a discussion of the politics of secularism in the Iranian Revolution of 1978–79.

This chapter explores the role of three global economic institutions (GEIs) in contemporary economic governance: the International Monetary Fund, (IMF), the World Bank and the World Trade Organisation (WTO). GEIs are key components of global economic governance, and their activities are central to the pursuit of accountability, efficiency and equity in the global economy. The impact of GEIs on states and societies is complex and widely varying assessments of the performance of these organisations can be found in the literature. Given the absence of theoretical consensus on the roles and functions of GEIs, the first part of the chapter examines competing perspectives on international organisations.

This chapter presents the outlines of a constructivist understanding of world politics. We begin with a discussion of state identity and explore how identity defines and bounds state actions. To illustrate this concept, we address issues central to the study of world politics: change, governance and security. Overall, our goal is to present a textured, layered understanding of the international realm based on a notion taken for granted in much of IR theory, meaning. Constructivism is the newest but perhaps the most dynamic of the main theories of international relations. Unlike liberalism and realism (see Chapters 2 and 3), which have taken their bearings from developments in economic and political theory, constructivism – like Critical Theory (see Chapter 4) – is rooted in insights from social theory (e.g. Berger and Luckmann 1967; Giddens 1984) and the philosophy of knowledge (Golinski 2005; Hacking 1999; Searle 1995).

This chapter considers the relevance of postcolonialism to the discipline of ‘international relations’ (IR). It argues that postcolonialism advances a powerful critique of traditional approaches to IR (see chapters on realism and liberalism) since it calls into question the discipline’s foundational ontological and epistemological assumptions. In particular, it challenges the dominant assumption that states are the basic units of IR and that we should examine the relations between these units in the context of an anarchical system. Postcolonialism refocuses our attention on the constitutive role played by colonialism in the creation of the modern world and sees international relations as hierarchical rather than anarchical. It sees academic disciplines such as IR – and Western rationalist, humanist and universalist modes of thinking in general – as complicit in reproducing colonial power relations and seeks normatively to resist practices of colonialism in its material and ideational forms, whether political, economic or cultural.

This chapter explains the legal and political features of the United Nations. It begins with a short introduction to the UN Charter, which shows the framework of international law that defines, limits and empowers the organisation. It then puts these into a more practical setting, which emphasises how the United Nations is at the same time an actor, a forum and a resource for governments.

This chapter provides a brief introduction to the ethics and laws of war. The first part outlines what international law and the ‘just war’ tradition say about war; the second explores the conduct of war; and the third examines two recent dilemmas as examples of moral and legal debate: the legitimacy of pre-emptive self-defence and the use of cluster bombs.

The purpose of this chapter is to introduce the contemporary political debates surrounding globalisation. It illustrates the main features of protests against the social consequences of a globalised economy, and it identifies some of the key political issues that scholars and students of International Relations must face when addressing the promotion of justice and effective governance within a more densely connected world.

This chapter tracks the emergence and acceleration of global environmental problems since the end of World War II and delineates the field of global environmental politics. It also introduces the proposed new geological epoch called ‘the Anthropocene’ and the concept of planetary boundaries along with the key global environmental discourses of limits to growth/degrowth, sustainable development/green growth, ecological security and environmental justice. The chapter then examines how scholars working in the major theoretical traditions of International Relations – realism, liberalism, Critical Theory, constructivism and English School theory – have approached global environmental challenges. The conclusion reflects on the pivotal roles of the United States and China in tackling global warming.

This chapter makes three main arguments. First, ideas and practices of diplomacy have a multi-millennial history – much longer than is generally thought. Second, this long history has been characterised by both continuity and change. As a result, diplomacy has been as much adaptive as resistant to change. And third, that diplomacy is not diminishing in importance. To assess these claims, the chapter first addresses the issue of defining diplomacy, before examining the evolution of diplomacy in terms that may be characterised broadly as pre-modern, modern and postmodern. Finally, the chapter evaluates the relationship between diplomacy and the study of international relations.

This chapter offers an historical grounding in interwar international relations. It tracks and analyses the progress of international relations in the period between World War I (1914–18) and World War II (1939–45), both of which are rightly seen as two major and formative conflicts in international history and indeed for the study of International Relations. It is sometimes assumed that the two World Wars were primarily European affairs, at least in their origins, and reflected the persistence of European predominance in a fast-changing world. Yet these were truly global and globalising wars, as reflected in their causes, courses and consequences, the technologies they employed and the ideas they helped generate. The period in between the wars was a turbulent and unstable one. It foreshadowed European decline and witnessed the rise of the United States, the challenge of the Soviet Union and the Far East and, more gradually, of peoples around the world subject to imperial rule – in short, the interwar period provided the foundations for the international system that developed over the following decades. Many of its contours are still visible today.

This chapter introduces the concept and practice of security in international relations. It explores the dilemmas faced by states, individuals and the global community by first looking at contemporary crises and disagreements about security; second, examining how security has been differently defined and focused; and third, surveying how different theoretical approaches have understood and analysed security.

This chapter reflects on the tradition of Western political thought known as realism. Its main purpose is to identify who realists are, and to explain what realism is in the study of international relations. The first part of the chapter introduces students to some important thinkers, both ancient and modern, ascribed to the realist tradition. It also identifies two broad strands of realist thought: ‘classical’ and ‘structural’ or ‘neorealist’. The second part investigates attempts to conceive realism as a unified theory and practice of international relations. It highlights realism’s central concepts of the state and anarchy before reflecting on realism’s normative dimension.