How air forces developed between the two world wars. Rearmament - creation of the Luftwaffe, expansion of the Russian Air Force, reaction of western democracies. Dress Rehearsals - the use of airpower in Abyssinia, Spain and China during the late 1930s. Technical developments - the development of the monoplane metal - framed fighter, bomber developments, and invention of radar meant that the bomber would not necessarily get through.