What is the climax of the story "War"?

The climax of "War" comes at the point that the bulky woman, bundled in her coat as she weeps that her son has been taken to the front to fight for the country in the war, suddenly turns to the old man and asks him, "Then...is your son really dead?"

In Luigi Pirandello's short story "War," the author captures the sentiment of the greatest tragedy of war: the terrible loss of beloved sons that parents experience.
This story begins while passengers waiting for the train at Fabriano to join the main line with Sulmonia in the morning watch as a bulky woman and her husband board. She has been crying as their son has been deployed to the front. Her husband explains that the young man is their only son. But, another passenger tells the couple, that parents cry who have more than one son, as well; it is all the worse for having more than one. Another traveler tells them, 

If Country is a natural necessity like bread of which each of us must eat in order not to die of hunger, somebody must go to defend it

He explains that people should not weep because their sons are defending the country. Further, he relates that before his son died, the young soldier wrote him that he was dying satisfied because he was leaving life in the "best way he could have wished." So, the father declares, this is why he does not even wear mourning clothes. Then, the other passengers congratulate him for his stoicism.

Hearing this man's words, the weeping mother seems to awaken as if from a dream. She feels now that it is not the others who cannot understand her when she has declared parents belong to their children, but she who has not been able to rise up as have the other parents who accept the deaths of their sons for the security of their country. So, turning to the man who has spoken so stoically and proudly of his son, she asks the old man, "then...is your son really dead?"

When the passengers hear this question, everyone stares at her. The old man is stunned; then, he seems to comprehend that his brave son is, indeed, gone. As his face contracts horribly, he quickly grabs his handkerchief and he weeps uncontrollably with "harrowing, heart-breaking, uncontrollable sobs."