Are the following people satanists?

I don't believe they're Satanist. Besides, LaVey Satanism is just another form of Atheism. Anyway, like most bands who talk or sing about the Devil or doing it for the shock factor or the media attraction.

Some being Megadeth, Slayer, Marilyn Manson, ect.

No and they never said they were. Real Satanic musicians who are open about it are King Diamond, Acheron and Marilyn Manson all members in the Church of Satan which is elite atheism and not inverse Christianity.

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.