How big of a difference would it make if Franco’s Spain allowed the Luftwaffe to have a safe haven to train its pilots up until around the D-Day landings in 1944? I’m thinking that it becomes a bigger advantage as the war drags on and Allied fighters are increasingly able to range deeper into occupied Europe. Big question is, does this allow the Luftwaffe to survive things like Operation Argument (Big Week) and remain as a much stronger force deeper into the war?