The History of the Chemical Warfare Prohibition in the Geneva Protocol
The language in which the Geneva Protocol proscribes the use ofchemical weapons is found in a number of earlier treaties. These attempts to outlaw chemical warfare reflected the abhorrence and outrage with which the international community reacted to the use of gas in the First World War. Among the different gases used by both sides in that war were various types of lachrymatory (tear) gases. The massive use of lachrymators—it is estimated that 12,000 tons of this gas were employed—suggests that the draftsmen of these treaties were well aware of the military uses of irritant chemicals.
(a) The Treaty of Versailles.—The first international treaty to use the terminology employed in the Geneva Protocol was the Treaty of Versailles. It provided in Article 171 that “the use of asphyxiating, poisonous or other gases and all analogous liquids, materials or devices being prohibited, their manufacture and importation are strictly forbidden in Germany.” (Emphasis supplied.) The French text of Article 171 used the word “similaires,” which is also true of all subsequent treaties that adopt the formula found in the Geneva Protocol. What meaning the draftsmen of the Versailles Treaty attached to this formula is not clear, because they did not discuss its meaning. That little significance can be attached to the slight divergence between the English and French texts of Article 171 is apparent, moreover, from the language of Article 172 of the treaty. It required Germany to disclose to the Allies “the nature and mode of all explosives, toxic substances or other like chemical preparations used by them in the war. . . . ” The French text of
Article 172 renders the more restrictive “or other like chemical preparations” simply as “ou autres preparations chemiques.”
(b) The Treaty on Submarine and Gas Warfare.—The Treaty on the Use of Submarines and Noxious Gases in Warfare, signed in Washington in 1922 by France, Great Britain, Italy, Japan, and the United States, provided in Article 5 that:
The use in war of asphyxiating, poisonous or other gases, and all analogous liquids, materials or devices, having been justly condemned by the general opinion of the civilized world and a prohibition of such use having been declared in treaties to which a majority of the civilized Powers are parties,
The Signatory Powers, to the end that this prohibition shall be universally accepted as a part of international law binding alike the conscience and practice of nations, declare their assent to such prohibition, agree to be bound thereby as between themselves and invite all other civilized nations to adhere thereto.
Although the Treaty of Washington never entered into force because France failed to ratify it, it was ratified by the United States. Most of the discussion in the Senate debate on the treaty related to submarine warfare and the question whether chemical weapons were more or less humane than other weapons. The only discussion concerning the nature ofthe prohibition laid down in Article 5 consisted of the following exchange between Senator James Wadsworth, Jr., and Senator Henry Cabot Lodge:
Mr. Wadsworth. ...I think article 5 is drawn somewhat carelessly.... The phrase “other gases” is all inclusive. It reads: “asphyxiating, poisonous, or other gases.”
Mr. Lodge. To be used in war.
Mr. Wadsworth. Yes; but there are gases used in war other than asphyxiating or poisonous gases.
Mr. Townsend. What for?
Mr. Wadsworth. For balloons, such as helium gas, and hydrogen. A strict construction would seem to prevent the use of any gas in war. Undoubtedly that is not meant. . . .
It would seem in the French text that the word “similaires” ties the matter up, but in the English text the equivalent of “similaires” is not used. That, however, is a point of comparatively small importance.25
As his remarks indicate, Senator Wadsworth was concerned lest the language of Article 5 be construed to apply not only to the use of gas as a weapon, but to any use of gas in war whatsoever. But neither he nor any other Senator inquired whether Article 5 prohibited the use of tear gas or any other irritant chemical. This is particularly noteworthy because the documents of the conference at which the treaty was drafted, and which were before the Senate, indicate that this question had been considered but had not been unequivocally resolved.
The proposal to include in the Treaty of Washington a provision relating to chemical warfare came from the United States Delegation, which was led by Secretary of State Charles Evans Hughes and included Senator Elihu Root. The deliberation on this agenda item took place in the Committee on Limitation of Armaments, which was chaired by Secretary Hughes. He introduced the discussion of this subject by reading a number of reports relating to chemical warfare. The first was prepared by the Committee’s own technical subcommittee. This report noted, among other things, that “the kinds of gases and their effects on human beings can not be taken as a basis for limitation.... [T]hat the only limitation practicable is to wholly prohibit the use of gases against cities and other large bodies of noncombatants . . . but that there could be no limitation on their use against the armed forces of the enemy, ashore or afloat.” The second report, prepared by the Advisory Committee of the United States Delegation, proposed that “chemical warfare, including the use of gases, whether toxic or nontoxic, should be prohibited by international agreement.” The next document to be presented by Mr. Hughes was a memorandum by the General Board of the Navy.30 It asserted that the use of gas was “almost universally condemned” if it violated “the two principles in warfare, (1) that unnecessary suffering in the destruction of combatants should be avoided, [and] (2) that innocent noncombatants should not be destroyed.” The Navy emphasized the following considerations:
Certain gases, for example tear gas, could be used without violating the two principles above cited. Other gases will, no doubt, be invented which could be so employed; but there will be great difficulty in a clear and definite demarcation between the lethal gases and those which produce unnecessary suffering as distinguished from those gases which simply disable temporarily.
The report accordingly closed with the declaration that “the General Board believes it to be sound policy to prohibit gas warfare in every form and against every objective, and so recommends.”31
Having presented these reports to the Committee, Mr. Hughes made the following statement:
[D]espite the conclusions reached by the subcommittee of this committee... the American delegation, in the light of the advice of its advisory committee and the concurrence in that advice of General Pershing . . . and of the specific recommendation of the General Board of the Navy, felt that it should present the recommendation that the use of asphyxiating or poison gas be absolutely prohibited.32
The resolution containing the text of what was to become Article 5 was introduced by Senator Root with the following prefatory remarks:
Mr. Root said that the chairman had asked him to prepare this resolution, pursuant to the recommendation of those military and naval authorities and advisory committees to which the American delegation was bound to pay the highest respect. There was an expression on this subject which presented the most extraordinary consensus of opinion that one could well find upon any international subject. He had drafted the resolution... in the language of the Treaty of Versailles which was subscribed to by the four of the five powers here and was appropriated and taken over by the United States and Germany in the treaty concluded between them on the 25th of August .... 
The resolution presented by Senator Root was adopted unanimously and, although it sparked some general discussion, no attempt was made to explore the intended scope of the prohibition formulated in Article 5.
Legally the most significant aspect of the history of Article 5 of the Treaty of Washington is that not one of the delegations present made any attempt to exclude irritant chemicals from the prohibition of this clause. The legal significance of this omission derives from two interrelated facts: First, the reports Secretary Hughes presented to the Conference addressed themselves specifically to these weapons. Second, two of the three reports recommended a prohibition of all chemical weapons. The United States Delegation relied expressly on these reports and specifically rejected, as too limited in scope, the recommendations of the technical subcommittee. It is therefore most unlikely that a government which believed that Article 5 did not outlaw all forms of chemical warfare would have failed to state its views to the Conference.
(c) The Geneva Protocol.—The Geneva Protocol was drafted at the Conference for the Supervision of the International Trade in Arms and Ammunition and in Implements of War, which was convened to consider the adoption of a comprehensive treaty relating to the international arms trade. Noting that the draft treaty before the Conference did not contain a prohibition against the export of chemical weapons, the United States Delegation submitted two alternative texts dealing with this subject.39 The first of these, after proclaiming that “the use in war of asphyxiating, poisonous or other gases, and all analogous liquids, materials or devices, has been justly condemned by the general opinion of the civilized world,” would have bound the Contracting Parties “to prohibit the export from their territory of any such asphyxiating, poisonous or other gases and all analogous liquids, intended or designed for use in connection with operations of war.” The other text provided that the Contracting Parties would “agree to control the traffic in poisonous gases by prohibiting the exportation of all asphyxiating, toxic or deleterious gases, and all analogous liquids, materials and devices manufactured and intended for use in warfare.” When serious doubts were expressed at the Conference regarding the practicability of controlling the exportation of these chemicals, since they had many peaceful industrial uses, the United States proposed a separate instrument embodying the provisions of Article 5 of the Treaty of Washington. This proposal was adopted and explains why the chemical warfare prohibition of the Geneva Protocol came to be drafted in the language of Article 5.
No attempt was made at the Geneva Conference to discuss the scope of this prohibition and no reference to tear gas or other irritant chemicals appears in the records of the Conference. The only evidence pointing to an intention to exclude such agents is the statement of the United States delegate (Congressman Theodore E. Burton), who, in urging the adoption of a prohibition on the export of chemical weapons, expressed “the very earnest desire of the Government and people of the United States that some provision be inserted in this Convention relating to the use of asphyxiating, poisonous, and deleterious gases,” and emphasized that a “prohibition of the exportation of these gases” would receive the “express approval” of President Calvin Coolidge. No significance was attached to this statement in the Senate when it debated the advisability of ratification of the Protocol. As a matter of fact, one of the arguments that was advanced in the Senate against the ratification of the Geneva Protocol was that it would prohibit the use in war of tear gases, even though they were harmless and had been adopted by “every intelligent police force in the United States.” And while the floor manager of the treaty did not fail to emphasize immediately that the Geneva Protocol did not apply to the use of tear gas by the police, he apparently believed that it outlawed the use of this gas in an international conflict.
-  For an analysis of the history of this language see Bunn, loc. cit. note 4 above, at 397—402;A. B. Overweg, Die Chemische Waffe und das Volkerrecht 64—89 (1937).
-  See A. A. Fries and C. J. West, Chemical Warfare 15—16 (1921).
-  Treaty of Peace between the Principal Allied and Associated Powers and Germany, signed atVersailles, June 28, 1919,  Great Britain, Treaty Series, No. 4; 13 A.J.I.L. Supp. 151 (1919).
-  An early English-language draft of a provision that subsequently became Art. 171 employed thephrase “or similar gases,” but this wording was changed to “or other gases” in the drafting committee.Bunn asserts that there is no indication that any change in meaning was intended when “other” wassubstituted for “similar.” Bunn, loc. cit., at 398. He uses this to support a restrictive interpretation of“other.” However, the broad sense in which the original term “similar” was used is clear when oneexamines the full text of the original provision. It read: “Production or use of asphyxiating, poisonousor similar gases, any liquid, any material and any similar device capable of use in war are [sic]forbidden.” 4 U. S. Foreign Relations, The Paris Peace Conference 1919, at 232 (1943). Emphasissupplied.
-  U. S. Senate, Conference on the Limitation of Armament 888 (1922); 16 A.J.I.L. Supp. 57(1922).
-  62 Cong. Rec. 4723-4730 (1922). 25 Ibid. at 4729.
-  U. S. Senate, Conference on the Limitation of Armament (1922).
-  Ibid. at 384—395. 3 Ibid. at 384—385.
-  29 Ibid. at 3 86. 30 Ibid. at 386—387.
-  31 Ibid. at 3 87. 32 Ibid, at 387-388.
-  Mr. Hughes. 2 Ibid. at 388. 3 Ibid. at 394.
-  36 It is true, of course, that Secretary Hughes spoke at one point only of an absolute prohibition of
-  “the use of asphyxiating or poison gas.” But this does not detract from the point being made in the text.
-  If the U. S. Government had in fact intended to limit the scope of Art. 5 to “the use of asphyxiating orpoison gas,” prudence would have dictated an unequivocal statement to that effect; and this preciselybecause the U. S. Delegation had expressly associated itself with the views of its advisory committee andthe General Board of the Navy.
-  See note 10 above.
-  1 92 5 Geneva Conference Proceedings at 155. 39 Ibid. at 779.
-  See, e.g., ibid. at 528—535 and 306—308. 2 Ibid. at 310.
-  42 Ibid. at 316. 4 Ibid. at 155.
-  44 See 68 Cong. Rec. 141-154, 226-229, and 363-368 (1927).
-  45 Thus, after Senator Borah, the floor manager of the treaty, assured Senator James Reed that the
-  Geneva Protocol did not apply to the use of tear gas by the police, the latter replied that it outlawed the
-  use of that gas in an international conflict, and then asked, “Would it not be more merciful, assumingthat we were at war with some Central American country, to win our battles by the temporary disablingof our enemies than to blow them all over their cactus plants... ?” Senator Borah answered thisquestion by asking, “If you put them to sleep for a limited period, unless you took them prisoners andheld them, they would be ready for battle the next day, would they not?” Ibid. at 150.