The relationship between change and international legitimacy is an important topic. History (international and national history) and legitimacy do not stand still but change over time. There is a relationship of mutual influence and dependency between the evolution of history, including the organization of international relations in it, and the evolution of legitimacy. As history evolves, the culture of legitimacy evolves; and as legitimacy evolves, history evolves. Keeping this in mind, the chapter first discusses the fact that scholars have tended to focus on the perceived importance of stability in analyses of legitimacy and change. Second, using that discussion as a foundation, the chapter contends that the goal of an international order should be the socialization of instability. Third, the chapter analyzes the relationship between the characteristics of an international order, or part of it, and the question of its change, including change and stability and their relation to legitimacy.

This chapter explores how international law and its legitimacy could be improved and made more aligned with the demands of justice. It focuses on two types of requirements. First, there are the principles and accompanying procedures on the basis of which actors ask their agency (and their rights) to be recognized by international law and its culture of legitimacy. These principles are consent, justification, accountability, consistency, representation and participation, and non-abuse of power. Second, there are the topics around which this quest for the recognition of agency (and rights) takes place. They are better universality of international law, human rights as a benchmark of the legitimacy of sovereignty, compliance/enforcement/accountability, and human rights supported by public goods. These two kinds of requirements have been at the center of the efforts to make international law more inclusive as well as more legitimate, and they need to be taken more seriously in the future.

As of the beginning of February 2025, Donald Trump has been president for just a few weeks, and already he has dramatically altered and impacted US foreign policy and the international system. In a matter of a few days, as part of his “America First” policy, Trump’s administration has reassessed and ended a number of the United States’ prior international commitments, including withdrawing from the World Health Organization (WHO) and the Paris Agreement on climate change. He has urged NATO allies to increase financial burden sharing, announced tariffs on imports against China, Canada, and Mexico, and sanctioned the International Criminal Court (ICC), arguing that it is improperly targeting US and Israeli individuals. He has also expressed an interest in buying Greenland and retaking possession of the Panama Canal, and suggested taking over Gaza and removing the Palestinian population. More generally, Trump is abandoning both the tenets of US foreign policy held for decades and the benchmarks of international legitimacy as outlined by international law. International competition tamed by cooperation is no longer the name of the game. Raw competition and leverage for one’s own benefit regardless of the impact on others appear to be the modus operandi of the new Trump administration.

Chapter 23 stresses that four sets of ideas need to be added to the principles and the topics of focus mentioned in Chapter 22. First, neither international order nor national order can be sustainable if the contradiction that exists today between, on the one hand, the celebration of human rights and, on the other hand, the tendency to treat individuals as disposable, deepens or simply persists. Second, the global justice agenda cannot credibly claim to be feasible if it does not factor in the views of the rest of the world. It is imperative to integrate what the non-West thinks. The ownership of a global agenda cannot be lopsided. Third, a cosmopolitan approach does not have to call for the removal or elimination of the state and sovereignty; rather, it is their reconceptualization and the application of this reconceptualization that are recommended. Fourth, institutional innovation will help implement this agenda.

Chapter 6 highlights a few implications for political legitimacy and the theory of legitimacy that can be derived from some of the key points that I have touched upon in Chapters 4 and 5. The implications include the following: (1) the character of a theory of political legitimacy is at the same time conservative and progressive, albeit more progressive than conservative; (2) the scope of evaluation and judgment that a theory of political legitimacy entails must avoid two dangerous paths: the first one is thinking that it is not possible to produce valid evaluations and judgments of legitimacy, and the second one is evaluating and judging all political situations from one’s own perspective; (3) evidence—that is, what people think and feel—can be called upon and mobilized for the evaluation and judgment of legitimacy; and (4) contemporary politics is especially relevant to the discussion of legitimacy.

This chapter is a short intellectual biography focusing on my interest and engagement in questions of political legitimacy over the years. The chapter is organized into three parts. I begin by discussing how the issue of legitimacy has been one of my key intellectual concerns ever since I started to do research on politics, initially in the context of the study of political and legal regimes in Latin America (Argentina, Chile, and Uruguay). Next, I highlight my understanding of political legitimacy as a responsibility and what this means for the evaluation and judgment of politics. This understanding builds on one of my previous books, Legitimacy and Politics: A Contribution to the Study of Political Right and Political Responsibility. Finally, I focus on how, gradually, in particular in connection with my work with the United Nations (UN), I became interested in the question of political legitimacy at the international level.

The issue of international membership introduces the related issue of international rights holding. International rights holding amounts to being “in”—that is, being recognized as legitimate and, as such, as having rights. But the membership process through which a collective actor gets “in” and comes to enjoy the status of rights holder also has a selective and exclusionary character. There is an interrelated process of denial of rights holding for other collective actors. An illustration of how international membership associated with international rights holding can have this selective and excluding effect is the impact of international law on rights holding in the framework of colonialism—an impact so significant that it continues to have a legacy today. Thus, the selective character of international membership has a cost for international rights holding not simply for the societies at odds with the requirements of statehood but also for their individual members.

Political legitimacy is highly important internationally—and probably increasingly so. The question of legitimacy is at the heart of some of the most vital and debated issues of international relations and international law. Think about the centrality of legitimacy with respect to just war theory, issues such as self-determination, the secession of a country and the creation of a new one, state recognition, tensions between the demands of national sovereignty and those of human rights, international humanitarian interventions, and so on. At stake in each of these situations is identifying what is the right course of action and what is legitimate and what is not—and how these situations are handled has an influence on the international system and its legitimacy. In this perspective, Chapter 7 shows that the significance of legitimacy at the international level unfolds in the context of the interactions between the national and international realms and the following distinctions: we/them, inside/outside, particularist/universalist, and system/society.

This chapter completes the act of setting the stage for the rest of the book by stressing the significance of the relationship between legitimacy and law, at the national level as well as at the international level. Legitimacy and law do not have a simple and straightforward relationship—far from it. Highlighting four features of this relationship helps shed light on the complexity of their relationship and serves as a preview of some of the issues that will be addressed throughout the book. These four features are the paradoxical character of the relationship between legitimacy and law; the unavoidable, yet at times, problematic role of values in the legitimacy–law nexus; the need for legitimacy and law to not be entirely captive of the power on which they depend; and the nature of these features for legitimacy and law at the international level.

This chapter focuses on the fact that a major difference between a change in an international order and a change of international order is that the scope and depth of the former are not as great as those of the latter—in other words, change unfolding in an international system is somewhat circumscribed. To reflect on a change in the international order and what this means for its legitimacy, this chapter focuses on three points. First, it examines some of the characteristics that facilitate change in an international system and what this implies for the sense of legitimacy. Second, it mentions the reforms that an international order and its legitimacy can adopt to respond to evolving pressures, alluding to the stress faced by the current international system in the last few years. Third, this chapter ends with an overview of the systemic risk to which the present international system is exposed.

In this book, I have tried to make sense of legitimacy at the international level, especially in relation to international law. I have paid a lot of attention to international law, in particular aligned with the demands of legitimacy and justice. But international law is only one aspect of the forces and the ecosystem that shape international order. Therefore, alone it cannot engineer the change that the international system requires today. This change has to be part of a more comprehensive approach. Here is not the place to offer a full account of the areas on which research could concentrate in the future to further encourage justice and legitimacy at the international level. However, it is worthwhile to present a general overview of these areas. In particular, three domains offer a possible road map for facilitating a constructive path forward: globalization, emotions and passions in social life, and the geopolitics of tomorrow.

The chapter discusses the issue of the evaluation of the validity of international legitimacy. This issue is important because it concerns how true international legitimacy can be distinguished from false international legitimacy, especially in the midst of change. This chapter concentrates on this matter, with its philosophical resonance, by looking into when international legitimacy, established or changing (change of/in an international system and its legitimacy), can really be considered valid or legitimate. Specifically, the following questions are addressed: First, does it make sense to examine the issue of the evaluation of international legitimacy (established or changing)? Second, if indeed it makes sense, what are the criteria that can be used to evaluate the validity of a claim or belief of international legitimacy? Third, what are the relevance and the modalities of application of this normative approach to international legitimacy (established or changing) across various periods and cultures?

The changes at play in the contemporary world bring about challenges that are impacting political legitimacy. They make legitimacy at the same time more problematic and more relevant, at both the national and international levels. From this perspective, how these changes and challenges are going to be addressed in the coming years is likely to determine, to a large extent, the evolution of political legitimacy—nationally and internationally. Among the changes and challenges underway, and their associated events and trends, I highlight the following eight: (1) the challenge of integration and disintegration, (2) the economic and financial challenge, (3) the geopolitical challenge, (4) the normative challenge, (5) the technological challenge, (6) the reassessment of globalization challenge, (7) the crisis of democracy challenge, and (8) the governance challenge. I unpack them in turn and, for each of them, allude to their possible meaning and implications for political legitimacy.