House of Braganza, and the British government promises never to recognize any other ruler. By the more recent treaty between the two powers, concluded at Rio Janeiro, in 1810, it was declared, "that the two powers have agreed on an alliance for defence, and reciprocal guaranty against every hostile attack, conformably to the treaties already subsisting between them, the stipulations of which shall remain in full force, and are renewed by the present treaty in their fullest and most extensive interpretation." This treaty confirms the stipulation of Great Britain to acknowledge no other sovereign of Portugal but the heir of the House of Braganza. The treaty of Vienna, of the 22d January, 1815, between Great Britain and Portugal, contains the following article:-"The treaty of alliance at Rio Janeiro, of the 19th February, 1810, being founded on temporary circumstances, which have happily ceased to exist, the said treaty is hereby declared to be of no effect; without prejudice, however, to the ancient treaties of alliance, friendship, and guaranty, which have so long and so happily subsisted between the two crowns, and which are hereby renewed by the high contracting parties, and acknowledged to be of full force and effect."

der those

The casus § 285. Such was the nature of the compacts of alliance fueris un- and guaranty subsisting between Great Britain and Portreaties. tugal, at the time when the interference of Spain in the affairs of the latter kingdom compelled the British government to interfere, for the protection of the Portuguese nation against the hostile designs of the Spanish court. In addition to the grounds stated in the British Parliament, to justify this counteracting interference, it was urged, in a very able article on the affairs of Portugal, contemporaneously published in the "Edinburgh Review," that although, in general, an alliance for defence and guaranty does not impose any obligation, nor, indeed, give any warrant to interfere in intestine divisions, the peculiar circumstances of the case did constitute the casus fœderis contemplated by the treaties in question. A defensive alliance is a contract between several States, by which they agree to aid each other in their defensive (or, in other words, in their just) wars against other States. Morally speaking, no other species of alliance is just, because no other species of war can be just. The simplest case of defensive war is, where our ally is openly invaded with military force, by a power to whom she has given no just cause of war. If France or

Spain, for instance, had marched an army into Portugal to subvert its constitutional government, the duty of England would have been too evident to render a statement of it necessary. But this was not the only case to which the treaties were applicable. If troops were assembled and preparations made, with the manifest purpose of aggression against an ally; if his subjects were instigated to revolt, and his soldiers to mutiny; if insurgents on his territory were supplied with money, with arms, and military stores; if, at the same time, his authority were treated as an usurpation, and all participation in the protection granted to other foreigners refused to the well-affected part of his subjects, while those who proclaimed their hostility to his person were received as the most favored strangers; in such a combination of circumstances, it could not be doubted that the case foreseen by defensive alliances would arise, and that he would be entitled to claim that succor, either general or specific, for which his alliances had stipulated. The wrong would be as complete, and the danger might be as great, as if his territory were invaded by a foreign force. The mode chosen by his enemy might even be more effectual, and more certainly destructive, than open war. Whether the attack made on him be open or secret, if it be equally unjust, and expose him to the same peril, he is equally authorized to call for aid. All contracts, under the law of nations, are interpreted as extending to every case manifestly and certainly parallel to those cases for which they provide by express words. In that law, which has no tribunal but the conscience of mankind, there is no distinction between the evasion and the violation of a contract. It requires aid against disguised as much as against avowed injustice; and it does not fall into so gross an absurdity as to make the obligation to succor less where the danger is greater. The only rule for the interpretation of defensive alliances seems to be, that every wrong which gives to one ally a just cause of war entitles him to succor from the other ally. The right to aid is a secondary right, incident to that of repelling injustice by force. Wherever he may morally employ his own strength for that purpose, he may, with reason, demand the auxiliary strength of his ally. (a) Fraud

(a) Vattel's reasoning is still more conclusive in a case of guaranty: "Si l'alliance défensive porte une guarantie de toutes les terres que l'allié possède actuellement, le casus faderis se déploie toutes les fois que ces terres sont envahies ou menacées d'invasion." Liv. iii. ch. 6, § 91.

neither gives nor takes away any right. Had France, in the year 1715, assembled squadrons in her harbors and troops on her coasts; had she prompted and distributed writings against the legitimate government of George I.; had she received with open arms battalions of deserters from his troops, and furnished the army of the Earl of Mar with pay and arms when he proclaimed the Pretender, Great Britain, after demand and refusal of reparation, would have had a perfect right to declare war against France, and, consequently, as complete a title to the succor which the States-General were bound to furnish, by their treaties of alliance and guaranty of the succession of the House of Hanover, as if the pretended king, James III., at the head of the French army, were marching on London. The war would be equally defensive on the part of England, and the obligation equally incumbent on Holland. It would show a more than ordinary defect of understanding, to confound a war defensive in its principles with a war defensive in its operations. Where attack is the best mode of providing for the defence of a State, the war is defensive in principle, though the operations are offensive. Where the war is unnecessary to safety, its offensive character is not altered because the wrong-doer is reduced to defensive warfare. So a State against which dangerous wrong is manifestly meditated, may prevent it by striking the first blow, without thereby waging a war in its principle offensive. Accordingly, it is not every attack made on a State that will entitle it to aid under a defensive alliance; for if that State had given just cause of war to the invader, the war would not be, on its part, defensive in principle. (b) 147

(b) "Dans une alliance défensive le casus fœderis n'existe pas tout de suite dès que notre allié est attaqué. Il faut voir encore s'il n'a point donné à son ennemi un juste sujet de lui faire la guerre. S'il est dans le tort, il faut l'engager à donner une satisfaction raisonnable." Vattel, liv. iii. ch. 6, § 90.

[147 Treaty Obligations to aid in Defensive Wars.-This reasoning makes the words "defensive war" substantially synonymous with justifiable war, or necessary war. As the parties to the treaty for aid in "defensive war" have declined to agree generally to aid each other in all wars, and have declined to make the justice or necessity of the war the test of their obligation to aid, it is certainly a fair argument that they intended to confine themselves to cases of defensive operations, where the territory of the ally is invaded or threatened with invasion, and so long as that danger exists, and to the extent that it exists. This furnishes a more convenient, practical, and satisfactory test than that of the justice or necessity of the war; and the latter test the parties declined to establish, when the terms appropriate for the purpose were obvious. It is not unusual, in national federations and compacts, to make provisions for cases of invasion, which are not applicable to any other state of a war. The opinion of Kent

Hostages

cution of

§ 286. The execution of a treaty is sometimes secured by hostages given by one party to the other. The most for the exerecent and remarkable example of this practice occurred treaties. at the peace of Aix-la-Chapelle, in 1748; where the restitution of Cape Breton, in North America, by Great Britain to France, was secured by several British peers sent as hostages to Paris. (a)

tation of

§ 287. Public treaties are to be interpreted like other Interprelaws and contracts. Such is the inevitable imperfection treaties. and ambiguity of all human language, that the mere words alone of any writing, literally expounded, will go a very little way towards explaining its meaning. Certain technical rules of interpretation have, therefore, been adopted by writers on ethics and public law, to explain the meaning of international compacts, in cases of doubt. These rules are fully expounded by Grotius and his commentators; and the reader is referred especially to the

(Comm. i. 50-52) seems to be, that a treaty obligation to aid in a defensive war cannot, as of right, be insisted upon, if the ally first actually declares and commences the war, whatever may have been the balance of right and wrong in the previous relations of the belligerent nations. The nation undertaking the obligation so worded is not bound to look beyond the fact that the war is commenced by its own ally. At the same time, Kent holds, that, even if the war be strictly defensive in its form, the guarantor is not bound to render aid, if justice is, in his opinion, clearly against his ally. (Ib. 51.) Woolsey seems also of opinion, that the defensive war referred to in such treaties is to be determined by its moral character, as a wardingoff of injustice, and not at all by its military character; and that the aid is due, if the war begins in offensive operations by the ally, provided they be necessary to anticipate injustice; and is not due, although the ally be invaded, if his cause is bad. (Introd. § 103.) But if the treaty is, in terms, to aid in all defensive wars, and the war is strictly a defensive war against an invasion, how can the ally refuse assistance, and still consider the treaty as binding? The true position in such a case is, that, while the treaty does require the stipulated aid, the misconduct of the nation which brought the invasion upon itself may be so gross as to absolve the other party from his obligation. In other words, if a nation chooses to make a clear agreement to lend aid in a defensive war, and the true construction of that term refers to the military character of the war, and not to its moral aspects solely, then the question of the causes of the defensive war is addressed, not to the construction of the treaty obligation, but to an excuse in ethics for not fulfilling the obligation.

For the arguments on the obligation upon the United States of the French treaty of 1778, see Tucker's Life of Jefferson, i. 414, 421, and Hamilton's Works, iv. 366, 382. As to defensive wars, in their military as distinguished from their moral character, see Halleck's Intern. Law, 329; Klüber, Droit des Gens, § 236; Phillimore's Intern. Law, iii. § 67; Kent's Comm. i. 50, note; Ortolan, Règles Intern. ii. 5; Rayneval, Droit Nat. liv. iii. ch. 2; Bello, Derecho Intern. Part II. ch. 1, § 3.] - D. (a) Vattel, liv. ii. ch. 16, §§ 245–261.

principles laid down by Vattel and Rutherforth, as containing the most complete view of this important subject. (a) 148

§ 288. Negotiations are sometimes conducted under Mediation. the mediation of a third power, spontaneously tendering its good offices for this purpose, or upon the request of one or both of the litigating powers, or in virtue of a previous stipulation for that purpose. If the mediation is spontaneously offered, it may be refused by either party; but if it is the result of a previous agreement between the two parties, it cannot be refused without a breach of good faith. When accepted by both parties, it becomes the right and the duty of the mediating power to interpose its advice, with a view to the adjustment of their differences. It thus becomes a party to the negotiation, but has no authority to constrain either party to adopt its opinion. Nor is it obliged to guaranty the performance of the treaty concluded under its mediation, though, in point of fact, it frequently does so. (a) 149 Diplomatic § 289. The art of negotiation seems, from its very nahistory. ture, hardly capable of being reduced to a systematic science. It depends essentially on personal character and qualities, united with a knowledge of the world and experience in business. These talents may be strengthened by the study of history, and especially the history of diplomatic negotiations; but the want of them can hardly be supplied by any knowledge derived merely from books. One of the earliest works of this kind is that commonly called Le Parfait Ambassadeur, originally published in Spanish by Don Antonio de Vera, long time ambassador of Spain at Venice, who died in 1658. It was subsequently published by the author in Latin, and different translations appeared in Italian and French. Wicquefort's book, published in 1679, under the title of L'Ambassadeur et ses Fonctions, although its principal object is to treat of the rights of legation, contains much valuable information upon the art of negotiation. Callières, one of the French plenipotentiaries at the treaty of Ryswick, published, in 1716, a work entitled De la manière de négocier avec les Souverains,

(a) Grotius, de Jur. Bel. ac Pac. lib. ii. cap. 16. Vattel, liv. ii. ch. 17. Rutherforth's Inst. b. ii. ch. 7.

-

[148 Wildman's Intern. Law, 176–185. Woolsey's Introd. §§ 109, 150.] — D. (a) Klüber, Droit des Gens Moderne de l'Europe, Part. II. tit. 2, § 1;. ch. 2, § 160. [149 See note 40, ante, on Mediation. Also, North American Review, April, 1866, article on International Arbitrations.] — D.