This history seeks to discover and record the mainstream of thought within the United States Air Force (and its predecessors) concerning the role to be played by air and aerospace power in a deadly struggle for national survival. It seeks to trace the development of a theme of institutional thought, describe the organizational framework in which the thinking took place, and identify individual thinkers and their ideas. In great measure this chronology is the story of dedicated professional men who were attempting to discover the capabilities and limitations of new forms of air and aerospace power and to relate these new characteristics of military power to the defense of the United States and its national interests. The story begins with the first heavier-than-air flight in 1903 and closes at the end of 1984. This ending date permits a coverage of Air Force thinking about counterinsurgency warfare and the military operations in Southeast Asia.A constant concern in developing the narrative has been the problem of how to present the matters under consideration in the most meaningful manner. Since ideas and concepts are frequently interpretations of facts and not facts themselves, a thinker may predict meanings before events transpire or, even more likely, continue over a period of years to draw interpretative meanings from the factual happenings of the past. Fundamentally, ideas often lack a temporal quality, hence a history of ideas lacks the neatness of a history of past events. It is possible that this history of ideas, concepts, and doctrine of air power should have been presented as an anthology of pertinent discourse with accompanying commentary. This technique, however, would have obscured a proper recognition of the circumstance wherein the developing Air Force was itself an excellent manifestation of air ideas. The notion of an anthology was, nevertheless, so persuasive that the author, as often as possible, has allowed the thinkers to speak for themselves an