As I understand it the political mistakes made from the signing of the Treaty of Versailles onwards until right through the thirties helped to create the situation which led to the rise of the Third Reich, and this has always been understood; Hitler hoped that Britain would not be involved and miscalculated here- events like the bombing of Dresden have always been controversial so I can't really see that anything new is being put forward here.

"Passivity" had been tried with the annexation of the Rhineland, Anscluss and the Sudetenland and Hitler may have been stopped in his tracks if the non fascist powers had been "non passive "a bit sooner.