The classical airpower theorists promoted air forces as a revolutionary new combat arm capable of destroying the moral resistance of the enemy. Speaking about the effects of aerial bombardment, Giulio Douhet said, A complete breakdown of the social structure cant but take place in a country subjected to this kind of merciless pounding from the air. The time would soon come when, driven by the instinct of self-preservation, would rise up and demand an end to the war.  Douhet and others focused on crushing the enemy's will to fight through direct attack on civilian populations. These early theorists developed their ideas in the aftermath of WWI, when operations were t constrained over fears of collateral damage or force protection. Leading up to WWII, American airpower theorists expanded strategic air attack to include destroying the opponent's material war making capacity. During WWII and the Cold War, airpower's primary mission was touted as strategic bombing with two intertwined targets: military-ecomic capacity and civilian populations.