The first air force was founded by Napoleon Bonaparte. The American Civil, Franco-Prussian, and First World Wars saw extensive use of balloons, but it was during the Second World War that the balloon saw more new and imaginative uses. Barrage balloons helped prevent incursions by enemy aircraft and new, ingenious uses were found for balloons, including dropping bombs (as used by the Japanese against the USA), destroying enemy aircraft, espionage, and other clandestine operations. For the first time, all of the uses of balloons at war are contained in a single volume."