By the time of the establishment of the American Government the practice of the nations with regard to their mutual obligations had begun to resolve itself into fairly well-defined principles. Among these was one to the effect that one state must prevent the use of its territory and resources for hostile attacks upon its neighbors with which it is at peace. In the beginning this rule was evolved from the relations of neutrality; for the more pressing needs of the time of war tended to crystallize usage applying to it, while other practice was still incoherent. But obviously the law thus defined was only a phase of the general duty of a state to prevent injurious and offensive acts against friendly countries. The obligation is based upon the complete and exclusive control which the sovereign is presumed to exercise over its subject persons and territory. The authority of the sovereign exists alike in time of war and time of peace; and the requirement of the law extends as well to normal relations as to the exceptional conditions of neutrality.

The growth of international law, both in precision and in scope, has been one of the marked features of the general development of law in the nineteenth century. It is true that even at the present day the reproach is often cast upon international law that its content is unsettled, its authority vague, and its method unscientific. But one has only to compare the standard text-books of the present day with the treatises that were quoted as authorities in the beginning of the nineteenth century to realize the great progress which has been made towards the establishment of international law upon a truly scientific basis. It cannot fairly be expected that international law should have as yet attained, or shall in the near future attain, the precision and definiteness of municipal law. The last decade of the century did indeed witness the first sitting of an international legislative body in the form of a conference at The Hague, which enacted what may be called international statutory law. But apart from the fact that this body was composed of the representatives of independent, not of federal, states, and therefore its rulings could not be final, the subject-matter with which it dealt was in many cases not such as would admit of definition and analysis after the methods of municipal law. The states composing the family of nations present differences of physical, mental and moral characteristics far more marked than those exhibited by the individuals within a given state, and it is but natural therefore that it should be correspondingly difficult to codify in a precise and scientific manner the rules governing their mutual relations. But while the difficulties attending the codification of international law cannot be denied, there is reason to believe that the growth of international law during the twentieth century will proceed towards its appointed goal as steadily as it has done during the nineteenth century.

The confusion of thought in which the modern world likes to dwell is nowhere greater than in those things which come within the survey of the peace movement. Even its most enthusiastic supporters are unable to show that their efforts have tended to make wars less frequent than heretofore. Neither can they prove that any nation has yet submitted a single question to arbitration over which it would have gone to war if the Hague Tribunal had not existed. They must honestly acknowledge that wars occur less often now than in the past, partly because a great number of questions, as, for example, those of nationality and of colonization, which formerly led to war have now, to a great extent, been solved, and partly because the civilized nations have reached such a stage in their development that they no longer are inclined to draw the sword for the comparatively unimportant objects for which they were unsheathed at a time when the death and ruin of thousands meant little to the government.

“The only government of this country, which other nations recognize or treat with, is the Government of the Union; and the only American flag known throughout the world is the flag of the United States.” The Government of the Union, as the only internationally recognized agent of the state, bears the responsibility for any violations of the rights which it owes to aliens, whether these rights are the result of treaty obligations or of international law.

The recommendation included in the Final Act of the Second Hague Conference provides for a preparatory committee to elaborate a program and adds: “This committee should further be entrusted with the task of proposing a system of organization and procedure for the Conference itself.”