Metaphors can be more elusive than they may seem, and there have been countless times in which a story just flies right over my head. Kurt Vonnegut has done this many times, but again, I attribute this to my life experience, or lack thereof. As we grow intellectually we start to see things that we never even remotely thought possible or never had any interest in because we couldn't grasp them, but once we become aware we see that they really aren't that difficult to understand at all.
In Vonnegut's "A Man Without a Country" most of the stories are his personal experiences throughout his life dealing with things as they seemed to him. He was very humble about trying to recall information of his past. To a lesser extent I can see this, but if I reread the book twenty years from now, I bet it'll be clearer.
Sometimes these stories convey ideas about the future of society that, if understood, are cogent beyond belief! Ray Bradbury was particularly good at this, and his work has really made an impression on me. A great example was a short story he wrote about a late night walk where he and a friend were just walking for a breath of fresh air (as fresh as it gets) and were questioned by a passing police officer as to why they weren't back home. It's as though their very presence anywhere outside the confines of societal expectations is subject to suspicion. This kind of stuff is really quite terrifying. While my experiences thus far may not be quite as extreme, I often am questioned for things I do simply because they're "too far out" for many people to readily understand. This needs to stop, but will it? Really makes you think, doesn't it?