A nation state is a political entity characterized by a defined territory, a permanent population, a governing body, and the capacity to enter into relations with other states. It represents the intersection of a distinct cultural or ethnic identity with political governance, often leading to a sense of national unity among its citizens. Nation states are fundamental to the modern international system, as they are the primary actors in global politics. They engage in diplomacy, trade, and conflict, shaping the world through their interactions. Examples of nation states include France, Japan, and Brazil, each with unique cultural identities and political structures.