International relations (IR) is the study of how governments, societies and global organizations interact with each other. It explores global decisions that impact us all – from war and peace to trade and the environment. IR is a multidisciplinary field that can be found in departments of politics, history, law and economics.
Often seen as a field of study that examines interactions between countries and their governments, international relations can also be a way to understand other groups such as multinational corporations, transnational interest groups, and non-governmental organisations. A key theme in IR is the balance of power between states. This can be understood in terms of anarchy – where no single country dominates – or hegemony – where some states play a self-consciously balancing role to prevent the rise of a dominant power. The term can also be used to describe a situation of global imbalance, where a powerful state unfairly benefits from the international system.
Some IR scholars use game theory to analyse such situations, and in particular to explain why states might behave in certain ways. For example, some of the assumptions of neo-realism are supported by game theory: that is, a state may have a preference for the status quo, because it feels disadvantaged by the rules and practices of the current international system.
Revisionist states, on the other hand, seek to fundamentally change the rules and practices of the international system, because they feel disadvantaged by the current one. This is a view of the world espoused by Donald Trump and other nationalist leaders who favour a transactional zero-sum international order.