§1. In the two preceding chapters I have been mainly engaged in working out in a summary form the chief subordinate rules in which the general principle of mutual non-interference may most fitly be realised, in its application to the existing circumstances of civilised States. In so doing, I have found it convenient to refer largely to the received rules and customary practices of States in their external relations, as the best way of giving definiteness to general maxims which a merely abstract consideration of the subject inevitably leaves somewhat vague.
In the function of the expositor of international law as commonly recognized, the relation of the two parts of the procedure just described---deduction from principles and ascertainment of accepted rules and usages---is inverted. The expositor of international law is primarily concerned with ascertainment of the rules of international behaviour, that can fairly be said to be received or ``established''---or, at least, of such of these rules as can claim to be ``laws''. He has only to refer to principles when he finds doubt and disagreement as to what rule actually is established, or when a novel case has to be discussed to which the established rules are not clearly applicable.
The importance of both elements of this work---the ascertainment of usage by reference either to the practice of nations or to clauses in treaties and admissions in argument, and the correction of usage by reference to principles seems to me undeniable; I cannot doubt that, without it, the moral opinion and sentiment of civilised mankind, and their consciousness of their common interest in the maintenance of international peace and order, would be even less effective than they now are in checking reckless encroachments and violent retaliations, and promoting a peaceful solution of minor collisions of interest among States. But---as was before said---it may be reasonably doubted whether any system of rules thus worked out is properly to be called ``law'': and, in fact, the propriety of this appellation has been emphatically denied in England by Austin and his followers, who consider that it ought rather to be called ``positive international morality''. The suggested term can easily be shown to be unsuitable: but I think that it is instructive to discuss the grounds on which its adoption is urged. For we shall find that the system of rules commonly called ``international law'', while it differs importantly both from the positive law of a modern State and from its positive morality, may be usefully compared to both, being more like the former in some points and the latter in others: and that we tend to gain a clearer conception of it by observing the points of likeness and difference in either comparison.
In making these observations it will be convenient to recall the relations between Law and Positive Morality as examined in Chapter XIII. I there pointed out the importance of comparing these two systems of rules, both (1) in respect of the motives by which conformity to them is sought to be secured, and also (2) in respect of their precision and systematic coherence. Let us take the former point of comparison first, and ask how far the sanctions of so-called International Law---the penalties attached to its violation---resemble the sanctions of the positive law established within a State, and how far they resemble the sanctions of positive morality. We can see at a glance that they resemble both legal and moral sanctions in important ways: the former in their possible intensity, the physical violence that they may include; and the latter in the indefiniteness of their source and the uncertainty of their infliction. It is doubtful what States will express disapproval of any breach of a recognised international rule, and whether any State will inflict any further penalty beyond expression of disapproval: but if any State does pass from words to deeds, it is likely to proceed to that extreme of physical violence which we call war.
In considering war, however, as the ultimate sanction of international rules, we are met by the distinction noticed in Chapter XV. between rules of strict international duty, to the performance of which a State may rightly be compelled by force, and rules of international courtesy or comity, the breach of which justifies---generally speaking---moral disapprobation and complaint, but does not justify the use of violence. This distinction corresponds broadly to the distinction between legal and merely moral obligations in the sphere of civil conduct: and I conceive that it is generally accepted in practical as well as theoretical discussion of international relations. For instance, to take a case of current interest (in 1891), I suppose that most American politicians hold that Canada ought not to hamper---as she has hampered---the free use of her fisheries by citizens of the United States: but I suppose most of them would admit that, according to the received rules of international law, she ought not to be compelled by threat of force to discontinue her restrictions;---or, to express it in the received phraseology, that her behaviour, though unfriendly, is not ``illegal'', and that the only ``legal'' mode of compelling her to alter it is by retaliatory acts of a similar kind---unfriendly, but not violations of strict right.[Back to:]