If the actual fragment does not need to change (i.e. , it is the same fragment class), I would have the activity call a method on that fragment rather than replace it (your scenario #2), assuming it exists. That's much less expensive at runtime, and it's probably simpler to code as well.
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.