very few, only nine in
all. Six of these are mountain or plateau states, like Switzerland and
Abyssinia, which have used the fortress character of their land to
resist conquest, and have preferred independence to the commercial
advantages to be gained only by affiliation with their peripheral
neighbors.

[Sidenote: Inland and coastward expansion.]

Central and peripheral location presuppose and supplement one another.
One people inhabits the interior of an island or continent whose rim is
occupied by another. The first suffers from exclusion from the sea and
therefore strives to get a strip of coast. The coast people feel the
drawback of their narrow foothold upon the land, want a broader base in
order to exploit fully the advantages of their maritime location, fear
the pressure of their hinterland when the great forces there imprisoned
shall begin to move; so they tend to expand inland to strengthen
themselves and weaken the neighbor in their rear. The English colonies
of America, prior to 1763, held a long cordon of coast, hemmed in
between the Appalachian Mountains and the sea. Despite threats of French
encroachments from the interior, they expanded from this narrow
peripheral base into the heart of the continent, and after the
Revolution reached the Mississippi River and the northern boundary of
the Spanish Floridas. They now held a central location in relation to
the long Spanish periphery of the Gulf of Mexico. True to the instincts
of that location, they began to throw the weight of their vast
hinterland against the weak coastal barrier. This gave way, either to
forcible appropriation of territory or diplomacy or war, till the United
States had incorporated in her own territory the peripheral lands of the
Gulf from Florida Strait to the Rio Grande. [See map page 156.]

[Sidenote: Russian expansion in Asia.]

In Asia this same process has been perennial and on a far greater scale.
The big arid core of that continent, containing many million square
miles, has been charged with an expansive force. From the appearance of
the Aryans in the Indus Valley and the Scythians on the borders of
Macedonia, it has sent out hordes to overwhelm the peripheral lands from
the Yellow Sea to the Black, and from the Indian Ocean to the White
Sea.[251] To-day Russia is making history there on the pattern set by
geographic conditions. From her most southerly province in Trans-Caspia,
conquered a short twenty-five years ago, she is