Most likely some piece of the cactus spine is still buried in your skin, causing irritation. If you can't see the piece yourself and get it out, it's something you should see a doctor about.
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.