Have a look at: dev.mysql.com/tech-resources/articles/hi... and en.wikipedia.org/wiki/Nested_set_model (for a first reading).
You should javascript tree library for this which can be generated from PHP code. See the following link, you can choose anyone. queness.com/post/1138/10-javascriptcss-t....
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.