Plutonium lasts a long time. It could from as far back as the New Mexico test in July 1945. Or from any of the tests from then until 1962 when atmospheric testing pretty well ended.
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.