Cartel of Sovereigns
Jurgen Brauer and Robert Haywood:
"The modern concept of a sovereign state rests on at least three fundamental attributes. First, the sovereign has legitimate authority. This refers to socially acknowledged and accepted power, not just to the potential arbitrary and monopoly use of coercive force. Ultimately, authority derives from some legitimizing source, both internal (acknowledgment and general acceptance by the people ruled) and external (recognition by other sovereigns). Second, the sovereign has supremacy. There is no authority above a sovereign. All authority within a sovereign's realm is inferior to it, and external authority exists only to the degree that a sovereign state conditionally accepts it by agreement with other sovereign states. And third, the sovereign has defined territory over which it exercises its supreme rule.
Today, sovereignty is understood as self-rule of a people over a given territory, however that rule is culturally sanctioned and operationally exercised. The central purpose of sovereignty is to facilitate governance within the realm, that is, to promulgate laws, issue regulations, establish rules, and devise enforcement mechanisms. Sovereigns operate as de jure equals to each other. The international system then consists of an assemblage of such self-ruling, territorially defined, mutually exclusive sovereignties. They protect their internal realms from each other by what amounts to a collusive cartel of sovereigns. No institutions exist above them to exercise legitimate, binding authority. All agreements among them are made as equals, are voluntary, and are revocable." (http://www.wider.unu.edu/publications/newsletter/articles/en_GB/05-09-brauer-haywood/)