Final answer:
The United States first attacked Normandy during the D-Day invasion on June 6, 1944.
Step-by-step explanation:
When the United States entered the war in Europe, it first attacked Normandy during the D-Day invasion on June 6, 1944. This marked the beginning of the liberation of Western Europe from German occupation. The American forces, along with British and Canadian allies, landed on the beaches of Normandy and launched a massive assault on German defenses.
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