DECLARATION OF WAR. A public proclamation in which one government de clares itself to be at war with another. In the United States, Congress alone has the power to declare war, and when that body votes for war with a foreign power, such a measure is con sidered tantamount to a declaration of war. Prior to the ratification of The Hague Con vention (q.v.) which provided for procedure in regard to the opening of hostilities, the doc trine that notice must be given an enemy be fore commencing hostilities had not been re garded as an obligation, and practice respect ing it had shown no uniformity. Owing to the world-wide use of the telegraph, submarine cable and wireless telegraphy and the wide diffusion of news by which every incident in the events leading to war are instantly pub lished, a formal declaration was scarcely deemed necessary or required by morality or interna tional law, and each belligerent was usually satisfied with announcing its warlike intentions to its own subjects and to neutrals. On the outbreak of war belligerents have usually fol lowed the custom of issuing a manifesto de scribing the events leading to the necessity for such a declaration and justifying their attitude, but such a document is not obligatory, though oftentimes useful. The Hague Convention, to which the United States subscribed, provides as follows: Amos I.—The oontraotiag powers recognize that hos tilities between themselves must not commence without previous and explicit warning, in the form either of a reasoned declaration of war or of an ultimatum with conditional declaration of war.
ARTICLE IL—The existence of a state of war must be Article IL—The existence of a state of war must be notified to the neutral powers without delay. and shall not take effect in regard to them until after the receipt of a noti fication, which may, however, be given by telegraph. Neutral powers, nevertheless, cannot rely on the absence of notifica tion, if it is clearly established that they were in fact aware of the existence of a state of war.
The first step after an endeavor to adjust the difficulties by diplomacy is an ultimatum, the non-compliance with which on or before the time limit set usually means the outbreak of hostilities, though often no absolute time limit is set. This happened in President
Wilson's demand on 25 June 1916 that Carranza, constitutionalist President of Mexico, imme diately release the American troopers captured in the encounter at Carrizal and make an early declaration as to his intentions regarding the American punitive expedition then in Mexico. Several days elapsed before Carranza replied and even then failed to answer fully, but this was overlooked since he evinced a desire to adjust the dispute diplomatically, thus removing the immediate pressing necessity for commenc ing hostilities. For legal purposes the date of the official opening of a war is usually stated in the declaration. In April 1898 the United States sent an ultimatum to Spain demanding her instant withdrawal from Cuba on pain of war. On her refusal, Congress, 25 April 1898, declared that a state of war between the two countries had existed since 21 April. The same condition obtained in the Russo-Japanese War, the Japanese Minister on 13 Jan. 1904 having presented a note to the Russian government requesting a prompt reply, implying that if there were an unreasonable delay, 'hostilities would be commenced by Japan. On 5 February telegraphic instructions were issued to the Japanese Minister to announce to the Russian government that Japan had terminated negotia tions relative to the proposed Russian conven tion, which communication was made the fol lowing day. On the 8th hostilities began at Port Arthur but the formal declarations of war were not issued until 10 February. When no direct notice is given war is held to date from the time when either party commits the first hostile act. In 1854, before the British Ambassador had withdrawn, a British fleet steamed into the Black Sea to compel the re tirement of the Russian fleet to Sebastopol. On the other hand in 1870 Bismarck received a formal notice from the French chargé, and in 1877 Russia sent a formal dispatch to Turkey. For the various declarations on the outbreak of the European War in 1914 see WAR, EURO PEAN. Consult Wilson, George G., tional Law) (New York 1910).