The Law of Nations or the Principles of Natural Law (1758)

Emmerich de Vattel

Of the Voluntary Law of Nations, as it Regards the Effects of Regular Warfare, Independently of the Justice of the Cause

§ 188. Nations not rigidly to enforce the law of nature against each other
ALL the doctrines we have laid down in the preceding chapter are evidently deduced from sound principles, — from the eternal rules of justice: they are so many separate articles of that sacred law, which nature, or the Divine Author of nature, has prescribed to nations. He alone whom justice and necessity have armed, has a right to make war; he alone is empowered to attack his enemy, to deprive him of life, and wrest from him his goods and possessions. Such is the decision of the necessary law of nations, or of the law of nature, which nations are strictly bound to observe. (Prelim § 7): it is the inviolable rule that each ought conscientiously to follow. But, in the contests of nations and sovereigns who live together in a state of nature, how can this rule be enforced? They acknowledge no superior. Who then shall be judge between them, to assign to each his rights and obligations, — to say to the one, “You have a right to take up arms, to attack your enemy, and subdue him by force;” — and to the other, “Every act of hostility that you commit will be an act of injustice; your victories will be so many murders, your conquests rapines and robberies?” Every free and sovereign state has a right to determine, according to the dictates of her own conscience, what her duties require of her, and what she can or cannot do with justice (Prelim. § 16). If other nations take upon themselves to judge of her conduct, they invade her liberty, and infringe her most valuable rights (Prelim. § 15); and, moreover, each party, asserting that they have justice on their own side, will arrogate to themselves all the rights of war, and maintain that their enemy has none, that his hostilities are so many acts of robbery, so many infractions of the law of nations, in the punishment of which all states should unite. The decision of the controversy, and of the justice of the cause, is so far from being forwarded by it, that the quarrel will become more bloody, more calamitous in its effects, and also more difficult to terminate. Nor is this all: the neutral nations themselves will be drawn into the dispute, and involved in the quarrel. If an unjust war cannot, in its effect, confer any right, no certain possession can be obtained of any thing taken in war, until some acknowledged judge (and there is none such between nations) shall have definitively pronounced concerning the justice of the cause: and things so acquired will ever remain liable to be claimed, as property carried off by robbers.

§ 189. Why they ought to admit the voluntary law of nations.
Let us then leave the strictness of the necessary law of nature to the conscience of sovereigns; undoubtedly they are never allowed to deviate from it. But, as to the external effects of the law among men, we must necessarily have recourse to rules that shall be more certain and easy in the application, and this for the very safety and advantage of the great society of mankind. These are the rules of the voluntary law of nations (Prelim. § 21). The law of nature, whose object it is to promote the welfare of human society, and to protect the liberties of all nations, — which requires that the affairs of sovereigns should be brought to an issue, and their quarrels determined and carried to a speedy conclusion, — that law, I say, recommends the observance of the voluntary law of nations, for the common advantage of states, in the same manner as it approves of the alterations which the civil law makes in the rules of the law of nature, with a view to render them more suitable to the state of political society, and more easy and certain in their application. Let us, therefore, apply to the particular subject of war the general observation made in our Preliminaries (§ 28) — a nation, a sovereign, when deliberating on the measures he is to pursue in order to fulfill his duty, ought never to lose sight of the necessary law, whose obligation on the conscience is inviolable: but in examining what he may require of other states, he ought to pay a deference to the voluntary law of nations, and restrict even his just claims by the rules of that law, whose maxims have for their object the happiness and advantage of the universal society of nations. Though the necessary law be the rule which he in variably observes in his own conduct, he should allow others to avail themselves of the voluntary law of nations.

§ 190. Regular war, as to its effects, is to be accounted just on both sides.
The first rule of that law, respecting the subject under consideration, is, that regular war, as to its effects, is to be accounted just on both sides. This is absolutely necessary, as we have just shown, if people wish to introduce any order, any regularity, into so violent an operation as that of arms, or to set any bounds to the calamities of which it is productive, and leave a door constantly open for the return of peace. It is even impossible to point out any other rule of conduct to be observed between nations, since they acknowledge no superior judge.

Thus, the rights founded on the state of war, the lawfulness of its effects, the validity of the acquisitions made by arms, do not, externally and between mankind, depend on the justice of the cause, but on the legality of the means in themselves, — that is, on everything requisite to constitute a regular war. If the enemy observes all the rules of regular warfare (see Chap, III. of this Book), we are not entitled to complain of him as a violator of the law of nations. He has the same pretensions to justice as we ourselves have; and all our resource lies in victory or an accommodation.

§ 191. Whatever is permitted to one party, is so to the other.
Second rule. — The justice of the cause being reputed equal between two enemies, whatever is permitted to the one in virtue of the state of war, is also permitted to the other. Accordingly, no nation, under pretense of having justice on her side, ever complains of the hostilities of her enemy, while he confines them within the limits prescribed by the common laws of war. We have, in the preceding chapters, treated of what is allowable in a just war. It is precisely that, and no more, which the voluntary law equally authorizes in both parties. That law puts things between both on a parity, but allows to neither what is in itself unlawful: it can never countenance unbridled licentiousness. If, therefore, nations transgress those bounds, — if they carry hostilities beyond what the internal and necessary law permits in general for the support of a just cause, — far be it from us to attribute these excesses to the voluntary law of nations: they are solely imputable to a depravation of manners, which produces an unjust and barbarous custom. Such are those horrid enormities sometimes committed by the soldiery in a town taken by storm.

§ 192. The voluntary law gives no more than impunity to him who wages an unjust war.
3. We must never forget that this voluntary law of nations, which is admitted only through necessity, and with a view to avoid greater evils (§§ 188, 189), does not, to him who takes up arms in an unjust cause, give any real right that is capable of justifying his conduct and acquitting his conscience, but merely entitles him to the benefit of the external effect of the law, and to impunity among mankind. This sufficiently appears from what we have said in establishing the voluntary law of nations. The sovereign, therefore, whose arms are not sanctioned by justice, is not the less unjust, or less guilty of violating the sacred law of nature, although that law itself (with a view to avoid aggravating the evils of human society by an attempt to prevent them) requires that he be allowed to enjoy the same external rights as justly belong to his enemy. In the same manner, the civil law authorizes a debtor to refuse payment of his debts in a case of prescription: but he then violates his duty: he takes advantage of a law which was enacted with a view to prevent the endless increase of lawsuits; but his conduct is not justifiable upon any grounds of genuine right.

From the unanimity that in fact prevails between states in observing the rules which we refer to the voluntary law of nations, Grotius assumes for their foundation an actual consent on the part of mankind, and refers them to the arbitrary law of nations. But, exclusive of the difficulty which would often occur in proving such agreement, it would be of no validity except against those who had formerly entered into it. If such an engagement existed, it would belong to the conventional law of nations, which must be proved by history, not by argument, and is founded on facts, not on principles. In this work we lay down the natural principles of the law of nations. We deduce them from nature itself; and what we call the voluntary law of nations consists in rules of conduct and of external right, to which nations are, by the law of nature, bound to consent; so that we are authorized to presume their consent, without seeking for a record of it in the annals of the world; because, even if they had not given it, the law of nature supplies their omission, and gives it for them. In this particular, nations have not the option of giving or withholding their consent at pleasure: the refusal to give it would be an infringement of the common rights of nations (Prelim. § 21).

This voluntary law of nations, thus established, is of very extensive use, and is far from being a chimera, an arbitrary or groundless fiction. It flows from the same source, and is founded on the same principles, with the natural and necessary law. For what other reason does nature prescribe such and such rules of conduct to men, except because those rules are necessary to the safety and welfare of mankind? But the maxims of the necessary law of nations are founded immediately on the nature of things, and particularly on that of man, and of political society. The voluntary law of nations supposes an additional principle, — the nature of the great society of nations, and of their mutual intercourse. The necessary law enjoins to nations what is absolutely indispensable, and what naturally tends to their perfection and common happiness. The voluntary law tolerates what cannot be avoided without introducing greater evils.