Dali has a famous "self-portrait" using the Mona Lisa: studiolo.org/Mona/MONA14.htm As you mention, Warhol's pop art borrowed images from magazines and designs of pop culture artefacts like soup cans. Here is an article discussing his influence on more recent artistic 'borrowers': theage.com.au/articles/2003/09/24/106408... John Curran is known for using magazing images also, as is de Kooning.
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.