International relations is the study of how states and their citizens interact globally. It includes the broader relationships of which such interactions are a part, and the institutions (state, intergovernmental and non-governmental) that oversee those interactions. The field seeks explanations of behavior that crosses national boundaries, and the underlying political and social conditions that make it possible.
The United States emerged from World War II energized and determined to shape the world order, in which it could prosper as the most powerful nation. This new policy, known as realist international relations, combined hawkishness about the need to project power abroad with idealism about the use of such power for liberal aims. It remains the dominant form of American foreign policy.
A long-term increase in global temperatures, caused by the burning of fossil fuels and other human activities. This is a central issue of international politics, with countries pursuing their own economic and security interests at odds with efforts to limit carbon emissions and slow climate change.
A negotiated settlement in a conflict, usually ending hostilities for a limited period. Examples include the Oslo Accords in Israel/Palestine, the Good Friday Agreement in Northern Ireland and the ceasefires in Yugoslavia and Sierra Leone. A disputed area of land between two nations, often marked by physical frontiers and culturally defined as the territory of a particular ethnic group. Such disputes are often characterized by tensions over resources and territory and may lead to military or terrorist interventions.