where were they from/headed??
Four months after Pearl Harbor the US was losing the war as Japan expanded into the Pacific. FDR decided that an audacious attack on the Japanese mainland (mostly Tokyo) was called for - mainly to increase morale in the US. Since there were no land bases not already in Japanese hands within the bombers' range he had Doolittle load B-25s on the USS Hornet, sail into Japanese controlled waters, and launch the planes off the carrier - which had never been done before. The attack was only a token: 16 bombers which caused little damage. The planes flew onto China and the idea was to land in an area that was still Chinese controlled - there was no way these planes could actually land on the carriers.
The Japanese were completely flummoxed as they knew land-based bombers were out of reach (except possibly from China). So, when asked in a press conference where the planes launched from, FDR as a joke said "Shangri-La" (the fictional city in the Himalayas in the book "Lost Horizon").
Interestingly the idea for the Doolittle raid was to mainly to boost morale. But it likely also had the effect of goading the Japanese to attack Midway - the closest US island to Japan - with the idea of drawing the (few) remaining US carriers into a one-sided battle. Little did the Japanese know that their codes had been broken by the US so the US carriers were ready for them. That, and 5 min of incredible luck on the US side brought the "Miracle at Midway" victory which, really, was one of the main turning points of the war.
