Great book.
Let me second that. First thing I thought of when I started reading about Bowe Bergdahl. There's also a kinship, I think, between this book and "Red Badge of Courage."
I have to admit that, Bergdahl or no, I haven't thought of Tim O'Brien in quite some time, but I did admire his earlier books (it looks like he really has slowed down since 2002). I actually saw him give a reading at U Michigan, most likely from The Things They Carried.
Incidentally, I'm making a list of books I ought to reread one day, and I think this one and The Things They Carried both belong.
In my "war novel" pantheon, it's right up there with Matterhorn.