Final answer:
The United States entered World War II after the bombing of Pearl Harbor, contributed to the Allied war effort, and ultimately helped defeat the Axis powers.
Step-by-step explanation:
The United States entered World War II after the bombing of Pearl Harbor by the Japanese on December 7, 1941. Prior to this event, the US had adopted a policy of neutrality, but the attack on Pearl Harbor forced the country into war. Following the attack, President Franklin D. Roosevelt declared war on Japan, and then on Germany and Italy, both allies of Japan.
The US entry into the war had a significant impact on the course and outcome of the conflict. The country mobilized its industrial capacity, providing essential war materials and equipment to the allied forces. The US military also played a crucial role in major battles, such as the D-Day invasion in Normandy, France.
The US entry into World War II marked a turning point in the conflict and helped tip the scales in favor of the Allies, leading to the eventual defeat of the Axis powers.
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