in February that "as a result of a decision of the Washington Conference, it has been decided that the use of gas in any form is inadmissible." Douglas observed that contradictory claims by historians and commentators surrounding the use of gas in Iraq were partly the product of an inaccurate September 1921 letter by J. A. Webster, assistant secretary at the Air Ministry, claiming that poison gas shells had already been used the army during the previous year's rebellion. In December 1921 the Air Ministry revised its position, stating that "it is not known whether [gas shells] were used by the Army". The Army General Headquarters (GHQ) in Baghdad had informed Percy Cox in November that "gas shells have not been used hitherto against tribesmen either by aeroplanes or by artillery". Douglas also noted that Churchill's forceful 1919 memo in support of gas had served to convince observers that weapons of mass destruction had been used when in fact they had not been, which ironically paralleled events in 2003. British policy The British 1914 Manual of Military Law stated that the rules of war applied only to conflict "between civilized nations". It stated that "they do not apply in wars with uncivilized States and tribes", but the British commander in any conflict he partook in should observe "the rules of justice and humanity", according to his own individual discretion. Some gas shells and protective clothing were shipped to British India in July 1919, with a further small shipment in January 1920, for use on the North-West Frontier. However, a requisition for 16,000 shells and 10,000 gas masks was blocked by Lord Sinha, the Under-Secretary of State for India. He believed that a first use of chemical weapons by British and Indian forces would have serious implications, both moral and political, and that chemical weapons should be used only in retaliation for an Afghan or North-West Frontier Tribal chemical attack. In India, a temporary Travelling Gas School was set up in September 1920, but the matter then lapsed. Britain had used gas weapons in the Middle East, most notably in the Second Battle of Gaza against Ottoman forces in World War I. On that occasion, the use of gas did not prevent a British military defeat. The use of tear gas, not "only the most deadly gases", was considered; as shown in a War Office minute of 12 May 1919 in