Maybe you left something out of your question because it's a little puzzling. Real guns are legal in California so why would replicas not be? Are you talking about a replica of an illegal gun like a fully automatic machine gun?
If so then yes a non functional replica would be legal but if police see it, expect them to act like it's real until proven otherwise Toy guns in CA must have a bright red plug in the end nowadays so it's visible as a toy from a distance. You can even own a real fully auto gun as long as it's been disabled but again if the police see it they will treat it as if it were real until proven otherwise.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.