Well if this is a "supposedly" question, then this is what I would feel. If incest has been natural since the dawn of man, I believe I would be able to accept it. But if we just now realized that it is natural and harmless, I would still not be able to accept the idea as the taboo would be too far ingrained into my psyche to change now.
Supposing it turned out that incest was natural and harmless" There is no supposing. It isn't natural and harmless Genetically, psychologically or socially, and it never will be in your lifetime. End of argument.
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.