First Hague Peace Conference

At the First Hague Peace Conference in 1899, Article 23(a) banned the use of poisons or poisoned arms and was ratified by the United States. A separate declaration banning asphyxiating gasses in shells was rejected by the United States even though the major European powers all signed it (Taylor and Taylor, 1985). 

Captain Alfred T. Mahan, a U.S. Navy delegate plenipotentiary, gave three reasons for opposing the additional restrictions (1) currently used weapons were despised as cruel and inhumane when first introduced, (2) since there were no current chemical weapons stockpiles, it was too early to ban them, and (3) chemical weapons were not any more inhumane than any other weapon. The 1907 Second Hague Peace Conference retained the ban against poisons.15... 

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