This thread was promped by the "Bismarck" thread which veered into a discussion of aircraft carriers and Germany.
I think there is little argument that, by 1933 (the point the Versailles Treaty began being openly disregarded), Germany was ill-suited (geographically, technologically, and operationally) for effective employment of aircraft carriers other than as targets for RAF airstrikes.
But what if Germany took the lead in this develeopment in WW1, giving them a wealth of experience and operational knowledge in this field in the interwar period?
In OTL, Germany put its major navial aviation scouting emphasis into zeppelins largely because of the advocacy of Peter Strasser and Hipper. By 1917-18 this proved to be a technological dead end, at least as long as the airships would be fulled with hydrogen and operations would be primarily in the lousy weather of the North Sea and North Atlantic.
However, what if Strasser died in a 1914 zeppelin crash and German fascination with the naval zeppelin died early? Germany fielded arguably the best floatplanes and flying boats of anyone in WW1 and certainly had the merchant stock and uncompleted battlecruiser hulls to experiment with aircraft/seaplane carriers. Like zeppelins, this might have been seen as a way to supplement Germany's small scout cruiser force and/or make up for numbers with new technologies.
Imagine the High Seas Fleet with an auxilliary force of converted merchants serving as seaplane tenders by 1916-17 and one or two Lutzow BC hulls completed as experimental full or half-deck aircraft carriers by 1917 shipping Hansa-Brandenburg floatplanes or wheeled Albatross fighters.
While this would probably not alter the naval balance in a sea engagement(I have difficulty believing a flight of primitive torpedo-armed floatplanes could sink a Queen Elizabeth at sea), what if the Germans risked all and went for a surprise attack at British forces berthed in Scapa Flow. Would this be possible? Could the results be shocking enough to affect the diplomatic course of the war?