[Sidenote:  Plains and political expansion.]

The boundless horizon which is unfavorable to a nascent people endows them in their belated maturity with the power of mastering large areas.  Political expansion is the dominant characteristic of the peoples of the plains.  Haxthausen observed that handicapped and retarded Russia commands every geographic condition and national trait necessary for virile and expansive political power.[1050] Muscovite expansion eastward across the lowlands of Europe and Asia is paralleled by the rapid spread of American settlement and dominion across the plains and prairies of the Mississippi Valley, and Hungarian domination of the wide Danubian levels from the foot-hills of the Austrian Alps to the far Carpathian watershed.  It was the closely linked lowlands of the Seine and Loire which formed the core of political expansion and centralization in France.  Nearly the whole northern lowland of Germany has been gradually absorbed by the kingdom of Prussia, which now comprises in its territory almost two-thirds of the total area of the Empire.  Prussian statesmen formulated the policy of German unification and colonial expansion, and to Prussia fell the hereditary headship of the Empire.

Lowland states tend to stretch out and out to boundaries which depend more upon the reach of the central authority than upon physical features.  We have seen American settlement and dominion overleap one natural boundary after another between the Mississippi River and the Pacific, from 1804 to 1848.  Russia in an equally short period has pushed forward its Asiatic frontier at a dozen points, despite all barriers of desert and mountain.  Argentina, blessed with extensive plains, fertile soil and temperate climate, which have served to augment its population both by natural increase and steady immigration (one-fourth of its population is foreign), has expanded across the Rio Negro over the grasslands of the Patagonian plain, and thereby enlarged its area by 259,620 square miles since 1881.  The statesman of the plains is a nature-made imperialist; he nurses wide territorial policies and draws his frontiers for the future.  To him a “far-flung battle line” is significant only as a means to secure a far-flung boundary line.

[Sidenote:  Arid plains.]

From these low, accessible plains of adequate rainfall, which at first encourage primitive nomadism but finally make it yield to sedentary life and to dense populations spreading their farms and cities farther and farther over the unresisting surface of the land, we turn to those boundless arid steppes and deserts which Nature has made forever the homes of restless, rootless peoples.  Here quiescence is impossible, the Voelkerwanderung is habitual, migration is permanent.  The only change is this eternal restlessness.  While the people move, progress stands still.  Everywhere the sun-scorched grasslands and waterless waste have drawn the dead-line to the advance of indigenous civilization.  They permit no accumulation of productive wealth beyond increasing flocks and herds, and limit even their growth by the food supply of scanty, scattered pasturage.  The meager rainfall eliminates forests and therewith a barrier to migrations; it also restricts vegetation to grasses, sedges and those forms which can survive a prolonged summer drought and require a short period of growth.