The Things They Carried by Tim O'Brien
This was my #9 selection. Something I've realized today is that apparently I like novelizations (or short story-izations) of real events, or semi-autobiographical works (e.g., Go Tell It on the Mountain), and apparently I also like stories/novels where the author blurs the lines between what is real and fiction by inserting himself into the works (e.g., The New York Trilogy). This collection of short stories is based in part on O'Brien's experiences in the Vietnam War. The blurring of the lines between fiction and non-fiction led to my believing for a while that this was non-fiction.

Only upon a second reading sometime later did I get it. O'Brien did this intentionally: "I set out to write a book with the feel of utter and absolute reality, a work of fiction that would read like nonfiction and adhere to the conventions of a memoir: dedicating the book to the characters, using my name, drawing on my own life. This was a technical challenge. My goal was to compose a fiction with the texture, sound and authentic-seeming weight of nonfiction." It's hard to explain, but I think he particularly got the "texture" right. The book feels the weight of the complicated question of morality.
One genre I don't have a lot of selections from is war novels, but in the couple of instances where I do, the Vietnam War is the subject. In college I had a focus on 20th century American history and politics, and, especially being at a liberal arts college, the Vietnam War was a big part of that. It indirectly led to an obsession with all things Vietnam for me, which I got to realize with our first trip to Vietnam in 2008 (and subsequent trips).
Somehow I have three copies of this book.
@KarmaPolice , should I send you one? It's only 233 pages.