for the closely grouped, sedentary farmers with their growing families the wide-ranging trader with his Indian or Tunguse wife and his half-breed offspring.  Under harsh climatic conditions, the fur trade alone afforded those large profits which every infant colony must command in order to survive; and the fur trade meant a wide frontier zone of scattered posts amid a prevailing wilderness.  The French in particular, by the possession of the St. Lawrence and Mississippi rivers, the greatest systems in America, were lured into the danger of excessive expansion, attenuated their ethnic element, and failed to raise the economic status of their wide border district, which could therefore offer only slight resistance to the spread of solid English settlement.[338] Yet more recently, the chief weakness of the Russians in Siberia and Manchuria—­apart from the corruption of the national government—­was the weakness of a too remote and too sparsely populated frontier, and of a people whose inner development had not kept pace with their rate of expansion.

[Sidenote:  Value of barrier boundaries.]

Wasteful exploitation of a big territory is easier than the economical development of a small district.  This is one line of least resistance which civilized man as well as savage instinctively follows, and which explains the tendency toward excessive expansion characteristic of all primitive and nascent peoples.  For such peoples natural barriers which set bounds to this expansion are of vastly greater importance than they are for mature or fully developed peoples.  The reason is this:  the boundary is only the expression of the outward movement or growth, which is nourished from the same stock of race energy as is the inner development.  Either carried to an excess weakens or retards the other.  If population begins to press upon the limits of subsistence, the acquisition of a new bit of territory obviates the necessity of applying more work and more intelligence to the old area, to make it yield subsistence for the growing number of mouths; the stimulus to adopt better economic methods is lost.  Therefore, natural boundaries drawn by mountain, sea and desert, serving as barriers to the easy appropriation of new territory, have for such peoples a far deeper significance than the mere determination of their political frontiers by physical features, or the benefit of protection.

The land with the most effective geographical boundaries is a naturally defined region like Korea, Japan, China, Egypt, Italy, Spain, France or Great Britain—­a land characterized not only by exclusion from without through its encircling barriers, but also by the inclusion within itself of a certain compact group of geographic conditions, to whose combined influences the inhabitants are subjected and from which they cannot readily escape.  This aspect is far more important than the mere protection which such boundaries afford.  They are not absolutely necessary for the development of a people, but they