If the answer is EACH of the three Hubs I'd doubt it but still possible.
If the question is in total its pretty probabbly that you'd reach the same amount of visits.
When people visit your hub they do it to read/understand/learn about something. If you split your hub into three you're of course changing the original hub which could tranbslate into different amount of visits. Why?
Less Complete content. Therefor perhaps it doesn't cover as much as what I'd be looking for, therefor less traffic.
Splitted interest. If I visit your hub it might be because it reffers to something I want to read, perhaps I am not looking for the entire story but rather just one part, therefor I wouldnt need to look into the rest.
Then again, it could also increase your hub as it'd be a more focused hub on what I need therefor it might be easier/more attractive to read when it only involves what I want.
There might be other reasons, though those are the ones that first come into my head :P.
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.