This is especially clear when examining books from past eras, where societal themes from the time often make their way into the book without the author's conscious intent. I'm sure it happens in modern writing as well, of course, but it is the contrast between those older works and modern society that allows us to glimpse such things.

I'm arguing this in general principle; it's been too long since I've read Dune for me to argue one way or another in your environmental debate.