The event that ended America’s isolationist policy was when German U-boats attacked American ships, causing American casualties. This sparked the realization that America could not stay neutral to the war in Europe, as it was directly affecting American lives and trade.
The event that sparked the end of America’s isolationist policy was A. German U-boats attacked American ships, killing over one hundred Americans. This event took place before the United States entered World War II. Until this point, the US wished to maintain its neutrality and stay out of the Europian conflict. However, the increased aggression and attacks on American ships by German U-boats led to a change in this policy. It made Americans realize that they could not simply ignore the war in Europe as it began to have direct implications on American lives and trade.
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