Young boy with nothing to do observes an anthill. Puts a stick through one of the small holes and lo and behold ants stream out. Pokes more holes and soon has the whole hive agitated. Imagines he is fighting a battle with the ants. Ants discover him and start coming up his legs. That night, while scratching the itchy welts on his feet, thinks, "What if I wrote a science fiction story about my battle with the ants?"
But ... there is more to [b:Armor|102327|Armor|John Steakley|http://d.gr-assets.com/books/1337817762s/102327.jpg|604650]. It does take its bursts of adrenaline from the action segments, but it also takes time for introspection and examining the feelings of the characters, though not to the extent of being touchy-feely. The book is like its main characters, hard on the outside but emotionally tender.
Personal impressions: There is a melancholy in the writing, and an anger at specific aspects of life, ostensibly associated with the military. I read in one of the reviews here on Goodreads (love the earnest folks of this online community!) that the author passed away before a sequel was completed. Maybe this is autobiographical? Not with respect to the Ant War, but in terms of the experiences of the two main characters. If you don't watch out, the underlying sadness could get to you.