With an effective tactical-operational concept,  the German air power theorists needed a strategic doctrine and organisation. Robert Knauss ( de ) , a serviceman (not pilot) in the Luftstreitkräfte during World War I, and later an experienced pilot with Lufthansa,  was a prominent theorist of air power. Knauss promoted the Giulio Douhet theory that air power could win wars alone by destroying enemy industry and breaking enemy morale by "terrorizing the population" of major cities. This advocated attacks on civilians.  The General Staff blocked the entry of Douhet's theory into doctrine, fearing revenge strikes against German civilians and cities.