If it true that "Secret societies" are responsible for organising world wars, what would they GAIN from this?

I recently read a book by a fiction author called Dean Koontz. The book was 'The Good Guy'. In it there was a 'secret society' who claimed that they control the world through inciting fear in people. When people are scared, they will do things they never would normally. Think about it, if you were held at gun point, you would do anything not to be held at gun point anymore. I'd recommend the book. You can probably buy it on Amazon really cheaply and it'll explain way better than I have!!