Red Mars, but not for the reason you are asking.
My mom bought the paperback edition for me when I was 9 years old, when I was first started reading sci-fi books (thank you Animorphs for that intro). It was my first real “adult book” and it’s been knocking around in my collection for 32 years, moved with me across the US, and various other moves. It’s probably the one book that has been in my collection the longest. I didn’t read it until I was in my early 30s and I enjoyed it. I read Green Mars too, but I need to finish the trilogy.
I am interested in his Ministry of the Future book and I’ll read it at some point.