This is two books in one: a fictionalized wartime memoir combined with a sci-fi mind bender about aliens to whom time is a curious wrinkle of mind. To these aliens, death is nothing more than a single brush stroke among millions on a moving canvas; somewhere in the multi-verse the dead still live. For here and for now, when they die, it's just a hiccup seen by human kind, to paraphrase the novel, in the same way that a man on a moving flatbed rail car might view a mountain range through a long metal pipe.
And so it goes.
An interesting aside: the rubes of Hicksville, MO. (also known as Republic Mo.) have recently banned this book from their High School curriculum for not giving due deference to the predominant local religion.