National sovereignty is the idea that independent nations, which have declared their independence, have an organized government and are self-contained, have a right to exist without other nations interfering. It is essentially the unspoken rule of a nation's right to exist.
Sovereign nations not only have the right to form governments, they have the right to defend themselves against those nations that pose a threat to their sovereignty. National sovereignty is a driving force behind the American ideal of independence. The colonists became very disillusioned over being taxed by England without being granted any sort of representation within the English government. So they decided to form an independent nation that would allow them to govern themselves. With the Declaration of Independence, the United States took the first steps toward becoming a sovereign nation.
With a growing emphasis on a more globally focused worldview and economy, some nations have expressed concern over infringements on their sovereign rights. Some leaders feel that increasing the powers of international organizations, such as the United Nations, and alliances, such as the European Union, is detracting from their ability to remain sovereign by imposing sanctions on individual economies and militaries and forcing them to make decisions for the greater global good rather than for the good of their own nations.