Final answer:
The US declared war on Germany in 1917 due to unrestricted submarine warfare and the Zimmerman Telegram. The war impacted American politics by expanding the federal government's power and society by mobilizing the population and promoting anti-German sentiment.
Step-by-step explanation:
The United States declared war on Germany in 1917 for several reasons. One of the main reasons was Germany's unrestricted submarine warfare, which resulted in the sinking of American merchant ships and the loss of American lives. Additionally, the interception of the Zimmerman Telegram, where Germany proposed an alliance with Mexico against the US, further fueled public sentiment in favor of war.
The impact of the war on American politics and society was significant. Politically, the war led to the expansion of the federal government's power and influence. It also brought about the passage of the Espionage Act and the Sedition Act, which restricted free speech and allowed for the prosecution of individuals for expressing anti-war views.
Socially, the war brought about the mobilization of the American population, with millions of men enlisting in the military, and women entering the workforce in large numbers to fill the labor gap. The war also led to the growth of anti-German sentiment, with German-Americans facing discrimination and suspicion. The war had a long-lasting impact on American society and politics, shaping the country in numerous ways.
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