maintain with advantage
a protective tariff, chiefly because the free trade within its own
borders was extensive. The natural law of the territorial growth of
states and peoples means an extension of the areas in which peace and
cooeperation are preserved, a relative reduction of frontiers and of the
military forces necessary to defend them,[316] diminution in the sum
total of conflicts, and a wider removal of the border battle fields. In
place of the continual warfare between petty tribes which prevailed in
North America four hundred years ago, we have to-day the peaceful
competition of the three great nations which have divided the continent
among them. The political unification of the Mediterranean basin under
the Roman Empire restricted wars to the remote land frontiers. The
foreign wars of Russia, China, and the United States in the past century
have been almost wholly confined to the outskirts of their big domains,
merely scratching the rim and leaving the great interior sound and
undisturbed. Russia's immense area is the military ally on which she can
most surely count. The long road to Moscow converted Napoleon's victory
into a defeat; and the resistless advance of the Japanese from Port
Arthur to the Sungari River led only to a peace robbed of the chief
fruits of victory. The numerous wars of the British Empire have been
limited to this or that corner, and have scarcely affected the
prosperity of the great remainder, so that their costs have been readily
borne and their wounds rapidly healed.

[Sidenote: Political area and the national horizon.]

The territorial expansion of peoples and states is attended by an
evolution of their spacial conceptions and ideals. Primitive peoples,
accustomed to dismemberment in small tribal groups, bear all the marks
of territorial contraction. Their geographical horizon is usually fixed
by the radius of a few days' march. Inter-tribal trade and intercourse
reach only rudimentary development, under the prevailing conditions of
mutual antagonism and isolation, and hence contribute little to the
expansion of the horizon. Knowing only their little world, such
primitive groups overestimate the size and importance of their own
territory, and are incapable of controlling an extensive area. This is
the testimony of all travellers who have observed native African states.
Though the race or stock distribution may be wide, like that of the
Athapascan and Algonquin Indians, and their war