Airpower revolutionised warfare in the twentieth century.1 Strategies became obsolete, armies and navies vulnerable, and weapons useless. It is often assumed that airpower had a universal appeal, and was bound to follow an equally universal trajectory: a strong, independent air force, a fleet of bombers, and a military doctrine based on strategic bombing. This assumption is wrong. It is true that in the United States, the air force became a powerful, distinct institution, in which bombers were crucial, and that it was founded together with a clear military doctrine based on strategic bombing. However, the French Air Force became a weak and dependent organisation that agreed to fulfill every loosely defined mission available, it promoted a multi-purpose aircraft, and rejected any doctrine. Why did the same revolution in warfare, the use of aircraft for military purposes, lead to such a different outcome in France?