Geneva Protocol retaliation

These reservations meant that in World War II, States acquired chemical and biological weapons so that they would be able to retaliate in kind should chemical or biological weapons be used against them. Acquisition and stockpiling of such weapons was not prohibited under the Geneva Protocol of 1925 which applied only to the use of such weapons in war. It thus became regarded, because of the reservations, as a prohibition of first-use . 

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