That eminent jurist, Chancellor Kent, says that the science of public law should not be separated from that of ethics, nor encourage the dangerous suggestion that governments are not strictly bound by the obligations of truth, justice, and humanity in relation to other powers, as they are in the management of their own local concerns. States or bodies politic are to be considered as moral persons, having a public will, capable and free to do right and wrong, inasmuch as they are collections of individuals, each of whom carries with him into the service of the community the same binding law of morality and religion which ought to control his conduct in private life.
The law of nations consists of general principles of right and justice, equally suitable to the government of individuals in a state of natural equality and to the relations and conduct of nations; the conduct of nations should be governed by principles fairly to be deduced from the rights and duties of nations and the nature of moral obligation; and we have the authority of lawyers of antiquity, and of some of the first masters in the modern school of public law, for placing the moral obligations of nations and of individuals on similar grounds, and for considering individual and national morality as parts of one and the same science.
The law of nations, as far as it is founded upon the principles of natural law, is equally binding in every age, and upon all mankind.
The law of nature, by the obligations of which individuals and states are bound, is identical with the will of God, and that will is ascertained by consulting divine revelation, where that is declaratory, or by the application of human reason where revelation is silent. Christianity is an authoritative publication of natural religion, and it is from the sanction which revelation gives to natural law that we must expect respect to be paid to justice between nations. Christianity reveals to us a general system of morality, but the application to the details of practice is often left to be discovered by human reason.
Justice is of perpetual obligation, and is essential to the well-being of every society. The great commonwealth of nations stands in need of law, and observance of faith, and the practice of justice.