Isn't It Ironic?

In the Oatmeal's take on irony and in the given definition, three types of irony -- verbal, dramatic, and situational/cosmic -- are addressed.

In "Once Upon a Time," Nadine Gordimer uses situational/cosmic irony to convey the necessity of a balance between extremes. The short story begins with the narrator introducing, "a man and a wife who [love] each other very much and [are] living happily ever after. They [have] a little boy, and they [love] him very much." Conflict is introduced when the possibility of dangerous riots upsets the wife. To maintain the peace-of-mind that is required in a happily-ever-after atmosphere, the husband installs burglar bars and an alarm system. The degree of the ferociousness of the security system increases as the family requires more and more home-defense mechanisms to maintain their peace-of-mind.

Finally, at the very end of the story when the family is living "happily-ever-after" amid serrated metal and jagged blades and flesh-tearing fangs, the little boy plays a game and accidentally becomes tangled in the system, and, "the man and wife burst wildly into the garden... [while] the alarm set up wail[s] against the screams [and] the bleeding mass of the little boy [is] hacked out of the security coil with saws, wire-cutters, [and] choppers." The ultimate doom of the little boy presents situational/cosmic irony because the security system that the man and wife set up to protect their family from any sort of harm results in the tragic and very graphic death of their son.

Gordimer most likely uses irony as opposed to direct narration in the short story to emphasize the tragedy of the situation and better convey the big picture. If the little boy had died in any other fashion, the message that resorting to extremes may not have been expressed. It is the parents' struggle to obtain absolute peace-of-mind that eventually kills their son, and this suggests that had the parents not obtained the most ferocious and threatening alarm system available, their son would still be alive. In conclusion, the irony optimally conveys that taking extreme measures is more likely to result in tragedy than in the intended outcome.