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An air raid campaign on 18 April 1942 conducted by the United States Navy against the Japanese capital of Tokyo during World War II. The raid was named after the then-lieutenant colonel Jimmy Doolittle, who planned and led the operation. It served as an initial retaliation for the Attack on Pearl Harbor four months prior.
The raid was conducted using 16 B-25 Mitchell medium bombers launched from the aircraft carrier USS Hornet (CV-8). The attack was conceived as a one-way trip, as the Mitchells would not be able to return to the USN carrier fleet to conceal their position and instead they will be landed in areas controlled by the Kuomintang-controlled China for extraction.
While the raid caused minimal damage to the Japanese, it provided significant moral and propaganda victory for the US, as the raid demonstrated that the Japanese home island is not safe from attack. This would ended up being one of the contributing factor for the Imperial Japanese Navy to attack the Midway island, resulting in the Battle of Midway.