They did, just not against enemy troops. Hitler was very explicit in that matter. It had been done to him in The Great War and he detested it. The death camps were a different matter entirely. read more
During World War II, international law did not actually bar the United States from using gas warfare—although America had signed the 1925 Geneva Protocol outlawing gas, the Senate had never ratified it. Yet every peacetime President from Warren G. Harding to Franklin D. Roosevelt had defined gas as immoral and pledged to abide by the agreement. read more
Poison gas was something which could have been used by both sides but nobody wanted to do that with the fear of its counterpart doing the same..Poland used it once in which few german civilians and soldiers died..But If Hitler had used that against his enemies then Britain would have use it against the Germans. read more
It seems like this would have at least significantly slowed down the Russian onslaught. Even Churchill, it is said, was prepared to use poison gas had the Germans landed in Britain earlier in the war. read more