The characteristics that qualify these variously comand historically differing entities as nation-states and distinguish them from other forms of social and political organization amount in sum to the independent power to compel obedience from the populations within their territories. The state is, in other words, a territorial association that may range in size , in population, and that claims supremacy over all other associations within its boundaries. As an association, the state is pecu-liar in several respects: membership is compulsory for its citizens; it claims a monopoly of the use of armed force within its borders; and its officers, who are the government of the state, claim the right to act in the name of the land and its people.

A definition of the state in terms only of its powers over its members is not wholly satisfactory, however. Alall states make a claim to supremacy within their boundaries, they differ widely in their ability to make good their claims. States are, in fact, often challenged by competing associations within their boundaries; their su-premacy is often more formal than real; and they are sometimes unable to maintain their existence. Moreover, a definition in terms of power alone ignores the fact that there are great differences among states in the structures they employ for the exercise of power, in the ways they use power, and in the ends to which they turn their powSome of these differences are explored in the discusthat follows of two general categories of nation-states: the unitary state and the federal state. Partly from administrative necessity and partly because of the presof territorial interests, nearly all modern states pro-vide for some distribution of governmental authority on a territorial basis. Systems in which power is delegated from the central government to subnational units and in which the grant of power may be rescinded at the will of the central government are termed unitary systems. Sysin which a balance is established between two auton-omous sets of governments, one national and the other provincial, are termed federal. In federal systems, the provincial units are usually empowered to grant and take away the authority of their own subunits in the same manner as national governments in unitary systems. Thus, although the United States is federally organized at the national level, each of the 50 states is in a unitary relationship to the cities and local governments within its own territory.

. A majority of all the world's naare unitary systems, including Belgium, BulFrance, Great Britain, The Netherlands, Japan, Poland, Romania, the Scandinavian countries, Spain, and many of the Latin American and African countries. There are great differences among these unitary states, however, in the institutions and procedures through which their central governments interact with their terri-torial subunits.

In one type of unitary system, decentralization of power among sub-national governments goes so far that in pracalthough not in constitutional principle, they resemfederal arrangements. In Britain, for example, there are important elements of regional autonomy in the relabetween Northern Ireland, Wales, and Scotland and the national government in London; and the complex system of elected local governments, although in consti-tutional theory subject to abrogation by Parliament, is in practice a fixed and fairly formidable part of the appara-tus of British government. In other unitary systems of this type, decentralization on a territorial basis is actually provided for constitutionally, and the powers of locally elected officials are prescribed in detail. Thus, the Japa-nese constitution specifies certain autonomous functions to be performed by local administrative authorities.

A second type of unitary system makes substantially less provision for territorial decentralization of authority and employs rather strict procedures for the central suof locally elected governments. The classic ex-ample of this type is France. Its system combines central supervision of local affairs through appointed officers with territorial representathrough locally elected governments.

A third type of unitary system provides for only token decentralization. In such cases, the officials responsible for managing the affairs of the territorial subdivisions are appointees of the central government, and the role of locally elected officers is either minimal or nonexistent.Examples of this kind of arrangement include Germany under Adolf Hitler and also several Communist coun

Federal systems. In federal systems, political authoriis divided between two autonomous sets of governone national and the other sub-national, both of which operate directly upon the people. Usually a consti-tutional division of power is established between the nagovernment, which exercises authority over the whole national territory, and provincial governments that exercise independent authority within their own territo-ries. Most of the largest countries in the world — Argentina, Australia, Brazil, Canada, India, the United States—are organized on a federal basis. Federal states also include Austria, Cameroon, Libya, Malaysia, Mexico, Nigeria, Switzerland, Tanzania, Venezuela, Germany and Russia.

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