I feel there's more to this story than you've told us. If you do normally get As for your work - presumably also from this professor? - then it seems strange that he would give you such a poor mark for this particular paper without explanation.
On the other hand, if your As have all been from other teachers, and this is the first time this teacher has seen your work, then either your other teachers have been too easy on you, or - yes, possibly - this professor is being unreasonably rude. Give us a little more background. It seems such an unlikely thing to happen without some reason.
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.