Question: Does anyone know how allied propaganda influences America's decision to delclare war on Germany in 1917? 

Answer: Woodrow Wilson and many Americans blamed the war on militarism, and this was a theme that figured prominently in anti-German propaganda throughout France, Great Britain and, from 1915 onwards, in the United States. The idea was that the Kaiser and his autocratic Prussian government had a thirst for military power and glory, and such goals took priority over the needs and wishes of the people. The implication was that a "democratic" government would not have instigated the war.\nAmerica's long-standing policy of isolationism left the United States reluctant to involve itself with what was popularly perceived, among the American public, as a European war.\nEarly in 1917, Germany resumed its policy of unrestricted submarine warfare. This, combined with public indignation over the Zimmermann telegram, led to a final break of relations with the Central Powers. After further U-boat attacks on American merchant ships, President Woodrow Wilson requested that Congress declare war on Germany.
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