>>112133412By the 1940s the KKK was long dead as anything other than some local chucklefucks in various cities using the name, much the same as it is today In the Civil Rights era up through around the late 70s it was a more of a thing (largely in the south and particularly in Alabama) but died out again.
The Klan got so big in the 1920s because it was less about nigger hatin' and more about WASPs pissed at all the Eyetalians and Pollacks and such bringing their blasphemous, idol worshipping Popery into good ol' Protestant America while simultaneously many of those WASPs were getting pushed out of the job market by those same immigrants as they were cheaper labor. Many would move up into the Great Lakes area to find work which is why it was especially big in states like Indiana and Michigan. It was also big among immigrant Swede populations as Swedes were protestant so they had no love for Catholic immigrants.
To be sure the KKK didn't like blacks either but for the most part the 1920s Klan was a nativist movement that tasked itself with upholding WASP culture and WASP morals. When D.C. Stephenson murdered Madge Oberholtzer that destroyed the Klan's image as law abiding moral guardians and then the Depression hit and nobody cared about immigrants taking jobs since there weren't any resulting in the Klan rapidly dying out.
Really my issue is just autism about the continued pushing of the myth of the Superman radio show destroying the Klan. It was irrelevant as a political force by then and it's debatable how much, if any, of the "secret language" the show exposed. The Klan was back as a force by the next decade so clearly the show, if it did anything at all, didn't do a particularly good job of it.