PROPOSED RULES FOR THE REGULATION OF AERIAL WARFARE BY JAMES W. GARNER Professor of Political Science in the University of Illinois When the World War, in which aircraft was employed for the first time on an extensive scale as an instrument of combat, broke out, there were few conventional rules and naturally little or no customary law in existence governing the conduct of hostilities in the air. There was, to be sure, the declaration prohibiting for a period of five years the launching of projectiles and explosives from balloons or by other new methods of a similar nature, signed at The Hague in 1899 and renewed in 1907 for a period extending to the close of the third peace conference. Since the third conference has never been convoked, the declaration may be regarded as still binding on the states which have ratified it, in a war in which both or all the belligerents are contracting parties. But it is significant that only about half the states represented at the second conference signed the declaration, and among those which did not were Germany, France, Russia, Spain and Italy. It thus happens that the principal military states of Europe are not parties to it and its value therefore is slight. In consequence of the so-called "solidarity" clause it was not binding upon any of the belligerents during the World War, not even upon those which had ratified it. In the second place, there is Article 25 of the Hague Convention of 1907 Concerning the Laws and Customs of War on Land, which declares that "the attack or bombardment by whatever means, of towns, villages, dwellings or buildings which are undefended, is prohibited." As is well known, the words in italics were added in 1907 to the corresponding article of the Convention of 1899 upon the proposal of the French delegation for the express purpose of prohibiting the bombardment of "undefended" places by means of aircraft. Unlike the declaration of 1907, regarding the launching of projectiles, its duration is unlimited, but like it, it has no binding force in a war in which one or more of the belligerents are not parties. For this reason it was not binding upon any of the belligerents during the World War. Different, however, from the declaration of 1907, the convention of 1 Compare Fauchille, "Le Bombardement Aérien," Revue de Droit International Public, t. XXIV, p. 66; Rolland, "Les Pratiques de la Guerre Aérienne," etc., ibid., t. XXIII, p. 505; and Merignhac, "Le Domaine Aérien," etc., ibid., t. XXI, p. 226. 2 Actes et Documents de la deuxième Conférence, t. III, pp. 15-16. Neither Bulgaria, Italy, Montenegro, Serbia, nor Turkey, all of which were belligerents during the World War, had ratified it. Nevertheless, it may be argued and has been argued, which it is a part has been ratified by most of the important military states of Europe. But even in a war in which the article is binding on all the belligerents, it would not likely be of any great value, because it is based upon the illogical and impracticable distinction between "defended" and "undefended" places. It forbids the bombardment by aircraft of "undefended" places only and thereby inferentially permits the bombardment of those which are "defended", but it lays down no test for determining when a place belongs to one or the other category. If the test which is generally accepted for distinguishing between defended and undefended places in land and maritime warfare be applied to aerial bombardment, it will lead to absurd results, because the existence of certain facts which give a city or town the character of a "defended" place in respect to land and naval bombardment cannot be justly said to have any such effect in determining the liability of a place to bombardment by aircraft. The stipulations of the Convention Relating to International Air Navigation, signed by the plenipotentiaries of the Allied and Associated Powers at Paris on the 13th of October, 1919, and which has now been ratified by the governments of ten of the signatory Powers and adhered to by one nonsignatory Power," are by its express terms binding on the parties only in time of peace. In any case, its rules relate only to international aerial navigation and not at all to the conduct of war. Certain writers have reproached the authors of the convention for not having occupied themselves that the article does not embody a new rule of international law but is merely declaratory of an existing customary rule and as such was binding on all the belligerents regardless of the status of the convention of which it is a part. Compare to this effect Fauchille, "Les attentats Allemands contre les personnes et les biens en Belgique et en France," Rev. Gén. de Droit Int. Pub., t. XXII, pp. 403-409; Pillet, ibid., t. XXIII, p. 21; Rolland, article cited, p. 509; and Garner, International Law and the World War, Vol. 1, pp. 20-21. German jurists themselves admitted during the World War that the stipulations of unratified conventions are binding when they are merely declaratory of the existing customary law. See to this effect Zitelmann in Modern Germany (p. 604), being an English translation of a German work entitled Deutschland und der Welt-Krieg; Strupp in the Zeitschrift für Völkerrecht, Vol. IX, pp. 281 ff.; Von Liszt, in the Frankfürter Zeitung for Oct. 29, 1916, and de Visscher, Belgium's Case, p. 66. There is room for doubt, however, whether Article 25 was merely declaratory of an existing customary rule of international law. 'See the table of ratifications in Scott, The Hague Conventions and Declarations of 1899 and 1907, pp. 236-239. * Compare Pillet, "La Guerre Actuelle et le Droit des Gens," Rev. Gén. de Droit Int. Pub. t. XXIII, p. 27. 'The ratifying Powers are: Belgium, Bolivia, France, Great Britain, Greece, Italy, Japan, Portugal, Jugo-Slavia and Siam. The only adhering Power is Persia. 'Article 38 of the convention, as modified by protocols signed in May, 1920: "In case of war, the provisions of the present convention do not affect the freedom of action of the contracting parties either as belligerents or neutrals.” I have analyzed and commented upon the provisions of this convention in two articles entitled "La Réglementation Internationale de la Guerre Aérienne," published in Nos. 4-6 of the Revue de Droit International et de Législation Comparée (1923–24). equally with the formulation of rules governing the conduct of aerial warfare. But apparently the conference either considered the task too large or doubted the expediency at that time of attempting to formulate a code of rules for the conduct of aerial warfare, considering the lack of respect shown by the belligerents during the recent war for the existing conventions. At the Fourth International Congress of Aerial Legislation, held at Monaco in 1921, the silence of the convention of 1919 on the subject of aerial warfare was the subject of some criticism, and it was decided to place on the program of the next congress, to be held at Prague in October, 1922, the question of the regulation of aerial warfare.10 At this congress, M. Hobza made a report in which he dwelt upon the urgent necessity of international regulation, indicated what he considered to be the principal ends to be sought by such regulation, and advocated the prohibition of certain methods of aerial warfare. The congress, after hearing his report, charged its comité directeur with the task of formulating an avant-projet concerning the rules of aerial warfare." The subject was again on the program of the congress at its meeting at Rome in October, 1923. It was likewise the subject of discussion at the thirty-first Conference of the International Law Association held at Buenos Aires in 1922. The Conference on the Limitation of Armaments, held at Washington in 1922, did not occupy itself at all with the question of the regulation of aerial warfare, and the treaty for the limitation of armaments signed by the Powers represented at the conference, contained no limitations either upon the number or the size of airships which the contracting Powers might keep or construct.12 However, a treaty was signed on the 6th of February, 1922, by Great Britain, France, Italy, Japan and the United States in which it was recited that the use in war of asphyxiating, poisonous or other gases, and all analagous liquids and materials or devices, having been justly condemned by the general opinion of the civilized world and having been pro * Compare the remarks of M. Henry-Coüannier in the Compte rendu du IVème Congrès de Législation Aérienne (1921), p. 29. M. Henry-Coüannier proposed that Article 38 be modified to read that in case of war the stipulation of the convention should not affect the freedom of action of the contracting parties when such action was "exercised according to the law of nations" (ibid., p. 41). But the congress did not approve the proposal. Compare the remarks of M. de Lapradelle (who took part in the drafting of the convention of 1919), ibid., p. 44. 10 There was some objection on the ground of expediency to the proposed discussion of the subject, but it was pointed out that conventions for the regulation of land and naval warfare had already been concluded and that there was no reason why aerial warfare should not be similarly regulated. In fact, considering the probable rôle and character of aerial operations during the next war, there was even more reason why it should be regulated by an international convention. See the remarks of M. Hobza, ibid., p. 221. 11 Ibid., pp. 221–225. 12 See the report of the American Delegation to the President of the United States, in which it was stated that such limitation was considered impracticable. Text of the report in this JOURNAL, Vol. 16, p. 190. 14 hibited by a convention to which a majority of the civilized Powers were parties, the signatories declared their assent to such prohibition, agreed to be bound thereby as between themselves, and to invite all other civilized nations to adhere thereto, to the end that the prohibition should be universally accepted as a part of international law, binding alike the conscience and practice of nations.13 The prohibition upon the employment of these agencies is general in character, and was evidently intended to forbid their use in aerial as well as in land warfare. In view of the prospect that in the wars of the future the airship will play an increasingly important rôle and that poisonous liquids and chemicals will be employed on an extensive scale and with frightful results, this prohibition, if generally accepted, will constitute a very important restriction on the conduct of aerial warfare. The five signatory Powers have ratified the treaty and it is therefore binding upon them in a war between two or more of them. But it would seem from the terms of the treaty that it would not be considered as binding upon one of them in a war with a non-adhering Power. It will be noted that the treaty forbids only the use of gases and analagous liquids, materials and devices; it imposes no prohibition or restriction whatever upon the operations of bombardment so long as a belligerent refrains from making use of these agencies in his bombarding attacks. Subject to this limitation, the whole matter of bombardment by land, sea or air was left untouched by the treaty. The Washington Conference, however, was not indifferent to the importance, not to say the necessity, of international regulation of the new methods of war to which the invention and perfection of aircraft have given rise, but for obvious reasons it did not feel competent itself to undertake the difficult task of formulating the regulations which it evidently felt to be desirable. In these circumstances the conference adopted the wiser course Is Text of the treaty in SUPPLEMENT to this JOURNAL, Vol. 16, p. 57. 14 Professor Slosson remarks, apropos of the rôle which chemistry and aeronautics are likely to play in the wars of the future, that a single airship with two men will be able to fly over a warship at great height and besprinkle its decks with a liquid so corrosive that three drops touching the skin of a man will be sufficient to kill him, and so persistent, that a small quantity lodging in its crevices will render the ship uninhabitable for days. Exhibit under the Auspices of the National Research Council, prepared by the Chemical Warfare Service, Washington, 1921. It was stated in the New York Times of March 3, 1921, that the Chemical Warfare Service of the United States had already discovered a toxic liquid so strong that three drops of it coming in contact with the skin of a man would cause his instant death and that "falling like rain from nozzles attached to airships the liquid would kill everybody in its path." Compare also the following from an article by Professor A. M. Low in the Nineteenth Century for Sept. 1923 (p. 356): “Various forms of poison gas more terrible than any at present, will be used and the question of protection will become a highly scientific one. Another weapon-incidentally my own invention-will be jets of water highly charged with electricity. . . . Aeroplanes will be equipped with electric impulse guns firing an enormous number of bullets a second, and no clumsy trailing aerials will be necessary to pick up wireless instructions." of entrusting the task to a body of legal and technical experts. Accordingly, a resolution, dated February 4, 1922, was adopted providing for the appointment of a commission of jurists composed of not more than two members representing each of the five Powers participating in the conference (Great Britain, France, Italy, Japan and the United States) to consider and report to each of the said Powers upon the two following questions: (1) Do the existing rules of international law adequately cover new methods of attack or defense resulting from the introduction or development, since the Hague Conference of 1907, of new agencies of warfare; and (2) if not so, what changes in the existing rules ought to be adopted in consequence thereof, as a part of the law of nations. The commission thus provided for was authorized to request assistance and advice from experts in international law and in land, naval and aerial warfare. It was agreed that when the report of the commission should be made, the signatory Powers would thereupon confer as to the acceptance thereof and upon the course to be followed to secure consideration of its recommendations by the other civilized Powers. By a subsequent resolution adopted the same day it was agreed that it was not the intention of the parties in providing for the appointment of the commission to report upon the rules of international law respecting new agencies of warfare or that it should review or report upon the rules or declarations relating to submarines or the use of noxious gases and chemicals already adopted by the five Powers represented at the conference.15 The views of the signatory Powers regarding the employment of these agencies of warfare having already been embodied in a treaty, there was no need for their reconsideration by the commission. The members of the commission chosen were John Bassett Moore and Albert H. Washburn for the United States; the Rt. Hon. Sir Rennell Rodd and Sir Cecil Hurst for Great Britain; Professors de Lapradelle and Basdevant for France; Senator Vittorio Ricci for Italy, and Baron Matsui and Mr. Matsuda for Japan. The Hague having been chosen as the place of meeting, the Dutch Government was invited to be represented, and Professors Struycken and Van Eysinga appeared as its delegates. In addition to the members of the commission, there was a considerable body of technical experts (more than fifty altogether) especially in military, naval and aerial matters. The commission held thirty plenary sessions in the Peace Palace, beginning on December 11, 1922, and ending on February 19, 1923. It was clear that the "new methods of attack and defense resulting from the introduction or development since the Hague Conference of 1907, of new agencies of warfare", which the conference had primarily in mind in providing for the appointment of the commission were those resulting from the invention and development of aircraft as instruments of combat. But the invention and perfection of wireless telegraphy, which though not an agency of destruction, had also taken place since 1907, and had played an 15 Texts of both resolutions in SUPPLEMENT to this JOURNAL, Vol. 16, pp. 74-75. |