“No matter what form a world government with centralized power over the whole globe might assume, the very notion of one sovereign force ruling the whole earth, holding the monopoly of all means of violence, unchecked and uncontrolled by other sovereign powers, is not only a forbidding nightmare of tyranny, it would be the end of all political life as we know it. Political concepts are based on plurality, diversity, and mutual limitations. A citizen is by definition a citizen among citizens of a country among countries. His rights and duties must be defined and limited, not only by those of his fellow citizens, but also by the boundaries of a territory. Philosophy may conceive of the earth as the homeland of mankind and of one unwritten law, eternal and valid for all. Politics deals with men, nationals of many countries and heirs to many pasts; its laws are the positively established fences which hedge in, protect, and limit the space in which freedom is not a concept, but a living, political reality. The establishment of one sovereign world state, far from being the prerequisite for world citizenship, would be the end of all citizenship. It would not be the climax of world politics, but quite literally its end.”