The world is divided geographically and demographically into mutually exclusive territories and political structures called states which are independent and sovereign in most cases. There are numerous bodies, institutions, unions, coalitions, agreements and contracts between these units of authority, but, except in cases where a nation is under military occupation by another, "all" such arrangements depend on the continued consent of the participant nations. Countries that violate or do not enforce international laws may be subject to penalty or coercion often in the form of economic limitations such as embargo by cooperating countries, even if the violating country is not part of the United Nations. In this way a country's cooperation in international affairs is voluntary, but non-cooperation still has diplomatic consequences.