I may or may not be a proper noun.
Humans have always gone to war. It's one of the most common themes in human history, and as such, has been the focal point of many major aspects of the human condition, our cultures, and even the stories that we tell.
Dear Donald, I've written to you before, but it's unlikely to have reached you. After all, I'm just one citizen and I didn't even vote; I sort of don't believe in it.