The control, direction and
administration of the nucleus is parallelled by the control, direction
and administration of the total complex--the empire and/or the
civilization.

The development from nucleus to empire and from empire to civilization
creates three sets of political problems: those arising from the
administration of the nucleus; those arising out of contacts between the
nucleus and the circumference, between the associates and dependencies
and the nucleus, and those arising out of the determination of the
associates and dependencies to sever their connections with the nucleus,
win their independence, and take part in the unceasing efforts to
establish new nuclei, win the unending power struggle and shift the
power center.

Relationship between nucleus and periphery are the normal outcome of the
expansion of a nucleus into an empire. Each growing urban center reaches
out for an extension of its territory; for the food and raw materials
required by a growing population; for markets that can absorb the goods
and services exported by the urban center to pay for its necessary
imports of food and raw materials.

Politically speaking, the essential problem is to maintain a
relationship that will keep the imports coming in and keep the exports
going out. Imports may take the form of plunder seized by the strong in
contacts and conflicts with weaker neighbors; tribute paid by the weak
to the strong at the insistence of the strong, or trade in which each
side gains something. Empire building involves all three methods.

In virtually all instances the nucleus is richer and stronger; the
periphery is poorer and weaker. In virtually all instances these
relative positions have been the outcome of military operations in which
each party has tried to impose its will upon its rivals. In each case
the spoils went to the victor, who forced defeated rivals to cede
territory, to pay tribute, to give hostages or in some other fashion to
agree upon a settlement that left the victor richer and stronger and the
vanquished poorer and weaker.

Politically speaking, the relation of nucleus to periphery was that of
superior to inferior. Where the discrepancy was very great it resulted
in a relation of master and vassal or even master and slave.

An empire or a civilization, consisting of a wealth-power center and a
periphery of associated and dependent territories and peoples, led to a
living-standard differential in favor of th