Do all serial killers have mental disorders?

It all depends on who you ask. Serial killers know what they are doing and that it is all bad except in rare examples. In my opinion someone that get involves in such actions have some kind of a mental disorder since normal and persons with some kind of mental disorder do not get involved in serial killing.

Serial killers are exemptions of society and a minority.

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.