This quote is an example of tremendous sarcasm. If we look at the context of the quote, we can see how this operates. The paragraph just before Kat says this quote to the narrator, the soldiers are made to practice saluting drill for an hour because one of the soldiers was not smart enough in saluting a major:
Today we have done an hour's saluting drill because Tjaden failed to salute a major smartly enough. Kat can't get it out of his head.
We see here another example of the conflict or gap in understanding between the old and the new, or the people in charge of the army and the war and the young soldiers that are brought in to actually fight it and die horrible deaths as a result. The whole story features the narrator's growing awareness of the emptiness of such concepts as patriotism and honour when faced with the reality of war that the older generation seems to know nothing about. Kat's remark is said half-jokingly and half-seriously and it indicates the way in which the priorities of the older generation, as represented by the major in this example, are completely different from the younger generation and seem divorced from the brute realities of war.