The story is a parable of the Vietnam War that the author lived and fought through. But it’s more than that because the way it cleverly paints a believable world including one of the very few presentations of the consequences of relativity realistically. The passage of time allows the author to play with changes in society while the war progresses and Malthusian dystopias, sexuality and drugs are used in clever ways.
The book goes beyond a Vietnam allegory and stands the test of time it is well done. The novel is also pleasantly brief and the pacing is good. The weak point is the somewhat thin characters but in the context of a war novel they still work.