Experienced and committed Airmen, some of whom had helped to develop air power during WW1, provided the theory and doctrine for the use of air power during WW2. This collection covers both US and UK air power leaders. These air power advocates were passionate in support of air power, none more so than US General Billy Mitchell who convincingly demonstrated to the US Navy that air power made battleships—that sailed without air cover—obsolete. Admiral Moffett worked through the US Navy system to establish US Naval Aviation. The UK’s Marshal of the RAF Hugh Trenchard was responsible for creating the RAF as an organisation that could not only provide air defence during the Battle of Britain but was also capable of carrying out strategic strikes against an enemy. 'Bomber' Harris, as Commander Bomber Command in WW2, built on Trenchard’s organisation to develop a strategic strike force that was capable of destroying German industry and morale. Bennett (who was too young to serve in WW1) established the RAF Pathfinder Force which by 1944 helped to make bomber command an outstandingly effective night bombing force. The history of each of these air power Leaders can provide valuable lessons, some of which are still be applicable today.