Let's say that Douhet has a bit more influence in military theory than he historically did. Not enough to cause much change to the starting forces of WWII, but enough so that the Germans engage in the mass use of air dropped chemical weapons during their strategic air campaign over Poland, and, following the Phoney War, the bomber forces of both sides engage in the mass use of chemical weapons, so far as is sustainable and appropriate for the targets. How does this effect the course of the Second World War? Does the Luftwaffe ignore RAF Fighter Command from the beginning in favor of a Mustard Blitz, and does a Blitz with chemical weapons knock Britain out of the war? How about decontamination efforts, both concurrent and post-war? Are the American and British strategic bombing campaigns significantly more effective and do they escalate to the use of biological weapons, such as Operation Vegetarian or the mass-use of anthrax on urban targets? Is there any great change to the effectiveness of the strategic bombing campaign against Japan?