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During the war a series of posters was produced to warn people that any indiscretion they may have with result in problems for soldiers at the front. Many US and British citizens were involved in the war effort in some shape or form. Whether they were working in a factory building bombs or working in preparing documents they all had access to information of some degree of importance. Therefore their governments encouraged them not to talk about their work outside of their workplace. Similarly, if a loved one sent them a letter from the front detailing their position they were asked not to discuss it. This was to keep valuable information away from Nazi spies.