My whole life experience feeds into my writing. I think that must be true for every writer. Clearly the Army and combat were major influences; just the same, you need to understand that many of the writers we have now couldn't load a revolver.
Some writers say they cannot write in front of a window; many say they cannot function without almost perfect quiet. A writer with only two hours a day can write in the back of an open truck on the Interstate.
I get a lot of people complaining about my ambiguity, often in cases which there is nothing ambigous at all. As far as I can see, people read it when they were half stoned and listening to the TV. Then they come back and say gee, it's impossible to figure out what's going on in a story.
I could speculate, but it would be just speculation and the kind of thing that you would get in with a science fiction story. And if I was doing a science fiction story then I would come up with what can go wrong with this system.
Have a short story feature two situations, and then let them solve each other.
You never learn how to write a novel. You just learn how to write the novel that you're writing.