Expected Beliefs

Plot twists are hard to pull off properly. For example, look at any romance story. Over the years certain expectations have developed about such matters. Everyone knows that by the end that the guy or girl will end up with whomever they have had their eye set on for the entirety
of the story, that's how everyone wants things to end up. There might be little twists in plot, more ups than downs in one plot than the other, but everyone knows that by the end the protagonist will have found and gotten whoever it is he is really looking for. In action stories, you know that the hero will always make it, because it just feels wrong any other way.

Short stories, in addition to having to deal with such matters typical of plot, must also deal with elements inherent to the short story form, mainly that there is a single pull. Essentially what amounts to one or two major scenes out of a novel become the entirety of a short story. As such things move faster and again, certain expectations are developed. For example, in most Science-Fiction short stories, the story's setting usually functions as a very flavorful backdrop that dictates names and descriptions of characters and actions, but nothing really relating to the pure plot. There is also the notion of the pull, the one thing that creates the story, the little "what if..." that serves as the grain upon which everything is built. Still though, what this does is allow for a certain suspension of disbelief that causes a reader to simply take certain details for granted.

In Philip K. Dick's short story "War Veteran" most of the plot revolves around two forces gearing up for a war while the intrigue of a veteran from this upcoming war arrives from the future. The expectation of this is that time travel, specifically the veteran's travel, is to be the grain of the story, and for perhaps the first two-thirds of the story, functions as such. However, near the end of the book, more pieces start to fall in place and a plot twist arrives, fairly unexpected. Thus, by exploiting his reader's expectations of both science fiction and short story structure, Philip K. Dick successfully hides the story's secret in plain sight, within an element that those familiar with either matter would simply take for granted and not give a second glance towards.