§1. I now pass to consider that part of the work of Government which is primarily external;---that is, which has for its end the maintenance of proper relations between the community governed and other communities and individuals outside it.
Assuming the existence of a group of independent States, approximately on the same level of civilisation, among whom a large part of the surface of the globe is divided up---the rest being either sea or in the possession of uncivilised or more imperfectly civilised peoples,---what general rules can be laid down for the conduct of the governments of such States in their dealings with foreigners?
Here, firstly, any one who begins to reflect on the accepted premises of political reasonings in such matters finds on the one hand a distinction between Rules of International Law and Maxims of Foreign Policy; and on the other hand he finds, almost equally current, a criticism of this distinction, on the ground that no code of rules applied to the action of independent states can properly be called ``law''. And certainly such rules lack the characteristics that we have noted as belonging to the law that regulates the internal relations of States. A group of independent States has no supreme judicature, by which any controversy as to the precise rules of international conduct actually established can be decisively settled: no common legislature, whose determinations in respect of new rules are habitually obeyed by the majority of such States: and no central executive able to crush any recalcitrant nation with irresistible force. Under these circumstances it may reasonably be questioned how far the distinction between ``legal'' and ``moral'' rules and sanctions---which is of so great and pervading importance in the regulation of civil relations within a community---can be consistently or usefully applied to international relations. This question, however, it seems best to defer until we have reached a fuller view of the system of rules of international conduct for which it is desirable to obtain---and not unreasonable to hope---general acceptance, and of the sanctions applicable in support of such rules. In the meantime, the fundamental distinction which I shall take will be between (1) Rules or Principles of International Duty, and (2) Maxims of National Policy within the limits defined by duty. In discussing the former I shall avoid applying the term ``legal'' at all to the mutual claims of States but it will be sometimes necessary to distinguish ``strict duties'', the violations of which are to be regarded as wrongs justifying war in the last resort if reparation is obstinately refused, from merely unkind or unfriendly acts or omissions, which are to be regarded as only justifying retaliatory unfriendliness and general disapprobation, but not breaches of international peace.
The relation between rules of international duty---whether ``legal'', or only ``moral''---and maxims of policy will correspond broadly to the relation between rules of duty and maxims of prudence, as applied in practical reasonings on matters of private conduct: and accordingly the rules of international duty will be understood to be determined with a view to the common interests of the whole group of States; whereas in framing maxims of policy we shall primarily consider the interests of a single State, supposed to be pursuing its own ends within the limits fixed by international duty. It will therefore be obviously proper to investigate first the principles of duty, reserving the maxims of policy for subsequent discussion.
But before we proceed to the first investigation, it will be well to face a fundamental difficulty, that may naturally suggest itself as we pass from the discussion of the principles of internal legislation and administration, which has so far occupied our main attention. So far as this discussion went, the mode in which practical application was to be given to the conclusions of theory was obvious and unmistakable. Whatever principles of internal legislation have been determined after full consideration to be best ought to be applied by the legislature of each State;---of course with due regard to its particular circumstances and conditions, to the evils of great and sudden change, and to the limits---of varying elasticity---fixed by the opinions, customs, and traditions of the society. There is, in a well-ordered society, a habit of unhesitating obedience to law, on which the legislators may generally rely, so long as they are careful not to transgress the limits just indicated. But when we turn to principles of international conduct, we find the case different. Even if all States were agreed on the rules which it is the common interest of all to have generally observed, this would not necessarily make it the clear duty of any one nation to observe them, when the primary effect of such observance would entail a material sacrifice of national interests, unless there is a reasonable prospect that the rules in question will be observed by other States in similar circumstances. And the difficulty of relying on this reciprocity, in a grave conflict of interests and passions, is so manifest that it led Hobbes to enunciate the famous paradox that in the relations of independent nations (or individuals) ``right and wrong, justice and injustice have no place''. It is true that this paradox---in the extreme form in which Hobbes stated it---is contradicted by experience. There are accepted rules of international duty, and the pursuit of national self-interest is restrained by them,---imperfectly, no doubt, but still to an important extent. Still, it may be urged that though independent nations and their governments are actually restrained by international usages and precedents, it does not follow that they will be affected by a theorist's exposition of principles: this, at any rate, it may be thought, must be a mere demonstration in the air, without any practical effect.
The answer is twofold. In the first place, usages and precedents are often doubtful and ambiguous: and when this is the case, reference is naturally and inevitably made to the principles supposed to underlie the accepted rules: and it is the special business of the theorist to state these principles with clearness and precision. Secondly, whether International Law is more similar to law proper or to positive morality, there can be no doubt that it undergoes change in details from time to time: and these changes are likely to be more beneficial in their effects, the more the rational principles on which they ought to be based can be made clear and obtain general acceptance.
Nor does it seem difficult to determine the required rational basis: since the two lines of reasoning which naturally suggest themselves for determining it, in accordance with the plan so far pursued, will lead to the same general result.
In the first place, the natural aims and purposes of independent groups of men, in relation to their physical environment and to each other, and their possible mutual conflicts, have obviously a broad and general similarity to those of individual human beings. The analogy does not, indeed, hold altogether: the unity of the most orderly and harmonious political community is never so complete as the unity of an individual man: and, in fact, as we shall presently see, the incompleteness of the unity of States is a main source of the special problems presented by international relations. Still, the analogy is sufficiently strong to render it reasonable to consider how far the accepted principles of civil order within a normal modern community are applicable to a society of independent States.
Now it will be at once evident that the absence of a supreme supervising government excludes the application of ``paternal'' interference, except of a kind that would be unhesitatingly rejected in the civil relations of sane adults. No one would propose that a single private individual, or voluntary combination of private individuals, should be empowered---except under the strictest governmental supervision---to interfere with another sane adult for that other's good; the danger of such control being exercised in the interest of the protecting individual or group would be thought to outweigh any possible advantage to the person controlled. And a similar danger renders this kind of quasi-paternal control generally inexpedient in the case of States, at least if they are at all equal in grade of civilisation, and sufficiently coherent internally to be regarded as united wholes. It may, indeed, be sometimes advantageous for a weak State to be placed under the protection of a group of its neighbours, through whose mutual jealousies it may thus secure greater practical freedom from interference than if it were left in nominally complete independence: but this is hardly analogous to what we have called ``paternal'' interference. Again, a semi-civilised State may sometimes gain more than it loses by being brought into a condition of semi-dependence on a more civilised neighbour; but in the historical instances in which this relation has been established it has usually been by a self-interested encroachment of the protecting State, acquiesced in, rather than approved by, other nations; and the general conditions of its legitimacy can hardly be distinguished from the conditions of legitimate conquest.
Socialistic interference, again, seems almost out of the question in international relations, for the simple reason that so long as the concert of nations is ineffectual to prevent any one nation from doing mischief to another---and the continual frequency of wars shows that it is ineffectual---it would be futile to try to use it for the harder task of compelling mutual positive services. States have, indeed, combined in various ways---for instance, by international postal arrangements---for the promotion of their common interests; and it is eminently desirable that they should so combine. But, at least among States on an equality and sharing the same civilisation, common action of this kind has always been effected by voluntary combination; and I conceive that this must continue to be the case until the reign of peace among independent nations is finally established.
We are left, therefore, with the principle of mutual noninterference---interpreted as including fulfilment of contracts and reparation for wrong done---as the principle exclusively. applicable to the obligatory relations of civilised States. And historically this has been in the main the accepted principle of what has been known in modern times as International Law---so far as it has been conceived to be determined on rational grounds, and not by mere usage of convention. When the real, though imperfect regulative influence that had previously been exercised over Western Europe by the unity of Christendom had finally collapsed in the religious wars of the sixteenth century, the need of establishing, on independent principles, a system of rules for the conduct of nations was strongly felt; and the void was supplied by the conception of the Law of Nature, which had been gradually formed in the development of mediæval thought, partly by tradition from Cicero through Augustine, and partly from the revived study of Roman Jurisprudence. According to this conception individuals---or at least heads of families---had lived before the formation of political societies, and would always live, apart from positive law, in a ``natural'' society, under a system of rights and obligations based mainly on the principle of mutual noninterference, as above defined. It seemed clear that nations having no common government must be members of such a ``natural'' society; and, accordingly, the jurists of the sixteenth and seventeenth centuries, especially Grotius, tried to systematise and complete on the basis of this Law of Nature the body of rules governing international relations that had gradually come to be accepted. The system thus framed commended itself to thoughtful persons generally in the seventeenth and succeeding centuries;---indeed, Maine speaks of the ``rapid, complete, and universal success'' of Grotius's treatise De Jure Belli et Pacis, as a ``great marvel''. And though the actual conduct of European States in these centuries has often deviated very widely from the recognised ideal of international duty, still the influence of this ideal has been sufficient to make it practically useful to work out in detail the application of the principle of mutual non-interference to international relations. Indeed, if this principle were discarded, it would be hard to find any other to which appeal could be made, on any question of international duty not decisively determined by precedents.
Before entering on this task it seems desirable to define more closely the sphere of application of the rules that we are about to lay down. I have already said that their observance cannot be regarded as strictly binding on States except in their dealings with other communities from whom reciprocal observance may reasonably be expected. But, in applying this maxim, a distinction has to be drawn between the general principles of abstinence from aggression and observance of compact,---applicable, as we have just seen, to the relations of individuals no less than to those of communities---and the detailed rules of international conduct, inevitably in some degree arbitrary, which have been accepted as the best attainable expression of these principles by the civilised States of Europe, and those of European origin in America. It would be unreasonable to expect exact observance of these particular rules---or of any other particular rules which this group of States may hereafter accept---from even civilised States outside the circle of European civilisation, unless such States have in some unmistakable manner sought and obtained admission into the European state-system. But the general principles on which these rules are avowedly based, are of much wider application. There seems to be no class of societies---civilised, semi-civilised, or savage---in dealing with which a civilised State can be exempted from the obligation to observe these principles, unless it has adequate grounds for expecting that they will be violated on the other side: though the precise forms of behaviour in which the general intention of avoiding injury to other communities will be most fitly expressed, will of course vary with the customs of these communities. In dealing, however, with uncivilised or semi-civilised communities difficult questions arise as to the interpretation of the.duty of abstinence from aggression, and the manner in which it is to be reconciled with the legitimate claim of civilised communities to expand into unoccupied territory, and their alleged right---or even duty---of spreading their higher type of social existence. The consideration of these difficulties I reserve for a subsequent chapter (XVIII.): in the present and the following chapter our attention will be mainly confined to the rules of mutual duty which it is desirable to maintain among civilised States.
It appears from what has been said that the main heads of international duty will coincide broadly with what we have taken to be the main heads of civil jurisprudence. We shall regard it as the primary duty of a State to abstain from injuring any other State or its members (1) directly, or (2) by interference with rights of property, or (3) by non-performance of contract; and these three rules of duty, viewed in another aspect, will constitute the primary international rights. But under all these heads important differences are to be noted, in the application of these principles to the relations of States. These differences arise chiefly from the following causes: (1) the incomplete definiteness of States as compared with individuals; (2) their incomplete coherence,---especially the complication introduced by the difference and possible conflict between the actions of a government and those of the individuals who owe it obedience; (3) the difference between governmental control of portions of the earth's surface and private ownership of land; (4) the impossibility of applying simply, in international relations, the principle that coercion invalidates a contract. The last-mentioned difference is connected with (5) the inevitable enlargement of the Right of Self-defence, in the case of independent nations, to a Right of War. For, carrying the analogy with civil rights further, we see that if a primary international right is infringed, the wronged State must be held to have a secondary right to reparation; and, if reparation is refused, or if the outrage is gross and deliberate, the exercise of force must be held to be legitimate for obtaining redress, and adequate security against repetition of the outrage. But in the absence of a common government of nations such exercise of force ordinarily leads to war: and we thus have to consider the bindingness of agreements imposed by the victor in a war on the vanquished, and also to consider how far and in what way the mutual relations of belligerents and neutrals can be regulated so as to minimise the mischiefs of war.
I proceed to examine more closely each of these differences and its effects---confining myself, for the present, as far as possible to the consideration of peaceful relations, and leaving the regulation of war to the following chapter.