Why does Ralph ask Jack why he hates him?

My take on this has always been the maturation of Ralph. Ralph asks Jack this simple question and Jack can't answer. Aside from the obvious power struggle Jack doesn't really know why he hates Ralph. Jack is unable to understand his rage. As Jack loses himself in anger, his depth of understanding becomes less and less. Jack's need to be in control spills over into the sadistic. Jack understands this the least of any of the boys.