Wait, the drill happens on September 1st every year... but it's also supposed to be a surprise because it's unannounced? Isn't that kind of a contradiction?
Okay, onto the review.
War and Japan's involvement in them is a reoccurring theme in this collection. So is self-interest. Those two specific themes really get hammered home in this story, where Randian self-interest is a virtue that gets encouraged not only in individual citizens but also by the wider forces controlling the city, who make weapons that hurt people abroad because they know that it could never come back to hurt them. Until, of course, the resurgence of the repressed. Which, by the way, let's consider that. Where is the horror in this story? Surely, some of it comes from the last panels showing a girl who has been stuck in a lifeless, deprived chamber for god-knows-how-long. And some of it comes from the actual scenes of death, and therefore from the terrorists. But the terrorists and the ending are on-screen for so little time in comparison to the main emphasis, the thrust of the horror: people running away from real, living humans, shoving past them to secure themselves a spot in the shelter. Unconcerned with the death of anyone save themselves. It's the "secure your own oxygen mask before helping others" thing but taken to a certain self-interested capitalistic extreme where you don't even help others secure their oxygen masks. I don't say capitalistic for nothing either! This entire town is a company town, constructed for the company, by the company. It represents, in short, the ideals of the corporation, and of capitalism as a whole. Reducing risk by constructing shelters rather than ending (profitable) wars, teaching everybody to save their own hide first and damn whoever is limping to find a shelter themselves, these are the ideals criticized in the story.