Sphere of influence

Political concept

In the field of international relations, a sphere of influence (SOI) is a spatial/geographic region, or set of polities or nations, over which a leader nation state or other geopolitically powerful organisation has a level of cultural, economic, military, or political influence or exclusivity. While there may be a formal alliance or other treaty obligations between the influenced and influencer, such formal arrangements are not necessary for a sphere to exist. Influence can be had through the use of hard as well as soft power.

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