I wrote a letter today in which the dictator referred to his race,
" As a fellow green I find you to be an @ss."
& I was confused as to when racial labels are capitalised.
"See those greens over there? That is where to meet."
"All green folks like beer."
"Are you Green, Black or White?"
"I am green"

So when are words or terms that refers to ones race or ethnic group capitalised? Should the word "green" have been capitalised in the sentence I wrote for someone?