exhaustion of the limited domestic supplies would follow, and in the meantime the cost to the domestic steel industry would be serious. Cost may be taken to represent the net result of human energy multiplied into raw material. The movement would therefore be anti-conservational. If each state in the United States were to start out to become entirely self-sustaining in regard to minerals, and by various regulations were able to prohibit the use of minerals brought in from without, or the export of its excess of minerals, the waste in effort and materials would be obvious. Nature has clearly marked out fields of specialization for different localities, and the effective use of mineral supplies is just as much a matter of specialization as the effective use of man's talents. If the United States, because of its vast copper deposits, is in a position to specialize in this line and to aid the world thereby, this should involve recognition of the fact that other countries are better able to specialize in other commodities,—thereby forming a basis for mutual exchange, which is desirable and necessary for world development.
This conservational argument against artificial barriers does not necessarily imply complete elimination of tariffs or other restricting or fostering measures. Within limits these may be necessary or desirable in order to maintain differences in the standard of living, or in order to permit the growth of infant industries; but to carry these measures to a point where they interfere with essential mineral movements determined by nature is obviously anti-conservational.
For some mineral commodities, international coöperation may prevent duplication in efforts and the development of excessive supplies in advance of the capacity of the world to use them. Partly because of lack of such coöperation, certain mineral commodities have been developed in such large quantities in various parts of the world that it may be many years before demand catches up with development. In the meantime, large and unnecessary interest charges are piling up. This financial loss measures the loss in effectiveness of collective human effort.