Answer:The United States was involved in WWII almost immediately providing funds and equipment to the Allied forces. But we did not actively join in the fighting til after Dec 7, 1941. The attack on Pearl was the one thing no one had taken into account. We no longer were separate from the war. At that point we then joined in the fighting. when Americans got involved in WW2 In world war 2, Americans got involved right after the Japanese attacked pearl harbor
