Do you put an before a word that starts with the letter x or a before x?

Nope! You don't say, "an xylophone" for example. It just sounds wrong, and trust me, people will notice after a while.

But it seems OK before words beginning with x like x-ray which sound as if they start with an e.

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.