§ 8. In an offensive alliance, made before the war, the ally engages generally to coöperate in hostilities against a specified power, or against any power with whom the other party may declare war. Where an alliance is made in general terms, without any specified conditions, limitations, or exceptions, does the casus foederis take place the moment the other party declares war? In other words, does such an offensive alliance differ in its binding effect from one contracted with a party already engaged, or on the point of engaging, in a war, the character of which is already known? Vattel says: "As it is only for the support of a just war that we are allowed to give assistance or contract alliances, every alliance, every warlike association, every auxiliary treaty, contracted by way of anticipation in time of peace, and with no view to any particular war, necessarily and of itself includes this tacit clause, that the treaty shall not be obligatory except in case of a just war. On any other footing the alliance could not be validly contracted." Mr. Wheaton says: "To promise assistance in an unjust war, would be an obligation to commit an injustice, and no such contract is valid." It would seem to follow, from this fundamental principle, that where one of two parties to an offensive alliance, made before the war, declares war against its enemy, even though that enemy be the very nation against which the alliance was formed, the other ally is to be allowed time to examine into the causes of the war; if it be a just war, all his engagements come into force; but if it be unjustly declared, his treaty obligations cease to be binding. (Vattel, Droit des Gens, liv. 3, ch. 6, § 83; Wheaton, Elem. Int. Law, pt. 3, ch. 2, § 15; Garden, De Diplomatie, liv. 6, sec. 2, § 2; Bello, Derecho, Internacional, pt. 2, ch. 9, § 1.)

§ 9. So, also, in a defensive alliance made before the war, the casus foederis does not take place immediately on one of the parties being attacked by an enemy. The other contracting party has the right, as indeed it is his duty, to ascertain if his ally has not given the enemy just cause of war, for no one is bound to undertake the defense of an ally, in order to enable him to insult others, or to refuse them justice. If he is manifestly in the wrong, his co-ally may require him to offer reasonable satisfaction; and if the enemy refuse to accept it,'

and insists upon a continuance of the war, the co-ally is then bound to assist in his defense. But without such offer of reasonable satisfaction, the war continues to be aggressive in character, and therefore unjust, and the ally may properly refuse to render the promised assistance, for the tacit condition on which such assistance was stipulated to be given, has not been observed, or, in other words, the casus foederis has not taken place. (Vattel, Droit des Gens, liv. 2, ch. 10, § 90; Wheaton, Elem. Int. Law, pt. 3, ch. 2, § 15; Bello, Derecho Internacional, pt. 2, ch. 9, § 1; Wildman Int. Law, vol. 2, p. 166; Garden, De Diplomatie, liv, 6, sec. 2, § 2.)

§ 10. If, on the contrary, a party to the defensive alliance, could call upon his ally to assist him whenever he was assailed, and without regard to the justice of the war, or the circumstances of the attack, there would be no difference between a defensive and an offensive alliance, for, as stated in the chapter on different kinds of war, many wars which are defensive in their operations are essentially offensive in their character and principles. In the words of Wheaton, "where attack is the best mode of providing for the defense 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 a 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." (Vattel, Droit des Gens, liv. 2, ch. 16, §§ 245-261; Wheaton, Elem. Int. Law, pt. 3, ch. 2, § 15; Wildman, Int. Law, vol. 2, p. 166; Grotius, de Jur. Bel. ac Pac., lib. 2, cap. 15, § 13; Bynkershoek, Quest. Jur. Pub., lib. 1, cap. 9; Garden, De Diplomatie, liv. 6, sec. 2, §2; Burlamaqui, Droit de la Nat. et des Gens, tome 5, pt. 4, ch. 3.)

§ 11. Admitting the principle laid down by Vattel, that every treaty of alliance contains the tacit clause that it shall not be binding, except in case of a just war, and that the co-ally has a right to decide for himself upon the character of the war, and whether or not the casus foederis has taken

place, it is only in case the war is clearly and obviously unjust that he can claim a release from the obligations which he voluntarily contracted. Whether the alliance be offensive or defensive, or both, if there be strong reasons to doubt the justice of the war, the ally is to be allowed time to examine it before he can be required to render the stipulated assistance; but, unless upon such examination, he find it manifestly unjust, he must comply with his engagements. Under ordinary circumstances, and in the absence of any proof to the contrary, he is bound to consider that his co-ally has just cause of war. In speaking of the tacit restriction, which Vattel says is necessarily understood in every treaty of alliance, Mr. Wheaton remarks that it "can be applied only to a manifest case of unjust aggression on the part of the other contracting party, and cannot be used as a pretext to elude the performance of a positive and unequivocal engagement, without justly exposing the ally to the imputation of bad faith. In doubtful cases, the presumption ought rather to be in favor of our confederate, and of the justice of his quarrel." (Vattel, Droit des Gens, liv. 3, ch. 6, §§79-82; Wheaton, Elem. Int. Law, pt. 3, ch. 2, § 15; Bynkershoek, Quaest. Jur. Pub., lib. 1, cap. 9; Bello, Derecho Internacional, pt. 2, cap. 9, §1.)

§ 12. We have already pointed out the distinction between treaties of alliance and treaties of limited succor and subsidy. In a treaty of succor, the ally stipulates to furnish certain assistance in troops, ships of war, provisions, or money. If the succor is to consist of troops, they are called auxilliaries; if of money, it is called subsidy. The rules already laid down, with respect to the casus foederis in treaties of alliance made before the war, apply equally to treaties of limited succor and subsidy. For the reasons there given, such treaties are not binding where the war is manifestly unjust. (Vattel, Droit des Gens, liv. 3, ch. 6, §92; Wheaton, Elem. Int. Law, pt. 3, ch. 2, § 15; Bello, Derecho, Internacional, pt. 2, ch. 9, §1.)

§ 13. Again, Vattel says that if the state which has promised succor finds itself unable to furnish it, this inability alone, is sufficient to dispense with the obligation. If, for example, one of the allies is engaged in another war, not contemplated by the alliance, and which requires his whole strength, he is absolved from sending assistance to his ally

in the war to which he is not yet a party. Again, if he has promised provisions, and his own subjects are suffering from famine, the casus foederis does not take effect; for he is not obliged to give another what is absolutely necessary for the use of his own people. It seems to us that a promise is none the less binging because of the inability of the promisor to fulfil his engagements. (Vattel, Droit des Gens, liv. 3, ch. 6, § 92; Wheaton, Elem. Int. Law, pt. 3, ch. 2, §§ 14, 15; De Felice, Droit de la Nat. et des Gens, tome 2, lec. 28.)

§ 14. It is also proper to remark that even where the casus foederis is admitted to take place, and the stipulated succors are furnished, the ally who furnishes them is not necessarily made a party to the war. "Where one state," says Wheaton, "stipulates to furnish to another a limited succor of troops, ships of war, money, or provisions, without any promise looking to an eventual engagement in general hostilities, such a treaty does not necessarily render the party furnishing this limited succor the enemy of the opposite belligereut. It only becomes such, so far as respects the anxilliary forces thus supplied; in all other respects it remains neutral. Such, for example, have long been the accustomed relations of the confederated cantons of Switzerland with the other European powers." (Wheaton, Elem. Int. Law, pt. 3, ch. 2, § 14; Vattel, Droit des Gens, liv. 3, ch. 6 §§ 81, 82; Ward, Law of Nations, vol. 2, p. 265; Martens, Precis des Droit des Gens, §§ 301, 302; Garden, De Diplomatie, liv. 6, sec. 2, §§ 2–5; Riquelme, Derecho Pub. Int., lib. 1, tit. 1, cap. 12; Bello, Derecho Internacional, pt. 2, cap. 9, § 1.)

§ 15. A distinction, however, must be made between simple treaties of succor and subsidy, and capitulations for mercenaries, like those formerly entered into by the Swiss. Auxilliary troops are usually under the general control and direction of the power which furnishes them, and which is, therefore, in a measure, responsible for their acts. But mercenaries, furnished under capitulations, usually engage in a foreign service for a stated period, and for stipulated pay and allowances, being entirely at the disposition of the power which employs them, that which furnishes them having no part in the conquests which are made, or in the negotiations

and treaties which are entered into. (Martens, Precis du Droit des Gens, §§ 301-303; Galiani, Dei Doneri dei Prin., etc., lib. 1, cap. 5, p. 145; Moser, Versuch, etc., b. 10, pt. 1, pp. 139, 140; Romainmatier, Histoire Militaire des Suisse, passim; Garden, De Diplomatie, liv. 6, sec. 2, § 2.)

§ 16. Vattel discusses the question, whether the limited assistance rendered to the enemy, under the obligations of a subsidy-treaty, is a just cause of war. If the ally of our enemy, he says, goes no further than to furnish the stipulated succor, and, in other respects, preserves toward us the accustomed relations of friendship and neutrality, we may overlook this cause of complaint. This prudent caution of avoiding an open rupture with those who render to our enemy certain limited assistance, previously stipulated for, has gradually introduced the custom of not regarding it as an act of hostility, especially where it is of a limited character. But, if prudence dissuades us from making use of a right, it does not thereby destroy the right itself. A cautious belligerent may choose to overlook certain offences, rather than unnecessarily increase the number of its enemies, and be influenced by considerations of expediency, in not enforcing the strict rights of war. It is, therefore, a question of policy, whether the assistance furnished an enemy shall be regarded as good and sufficient cause for declaring war against the ally who furnishes it. (Vattel, Droit des Gens, liv. 3, ch. 6, §§ 79-82; Wheaton, Elem. Int. Law, pt. 3, ch. 2, § 14; Ward, Law of Nations, vol. 2, p. 295; Heffter, Droit International, §§ 115–117.)

§ 17. We have described, in another chapter, the general character of treaties of guarantee and surety, as distinguished from ordinary treaties of alliance. The question to be considered here, is, how far such treaties bind the party making the guarantee to assist the other party in a war for the defense or the security of the thing guaranteed? For example, Great Britain, by the treaties of 1642, 1654, 1661, 1703, 1807, 1810, and 1815, with Portugal, guaranteed the latter kingdom to the lawful heir of the house of Bragansa, and agreed to defend it "against every hostile attack." In the case of a war between Portugal and a third power, in which the former was subjected to "a hostile attack," was Great Britain bound