KANTOREK: You are the life of the fatherland, you boys. You are the iron men of Germany. You are the gay heroes who will repulse the enemy when you are called upon to do so.
Chauvinism impresses the idea that country is the only thing that matters. The individual students don't matter to Kantorek because all he can see in them is the "life of the fatherland."
MUELLER: I think maybe the Kaiser wanted a war.
TJADEN: You leave us out of this.
KAT: I don't see that. The Kaiser's got everything he needs.
PETER: Well, he never had a war before. Every full-grown emperor needs one war to make him famous. Why, that's history.
PAUL: Yeah, generals, too. They need war.
MUELLER: And manufacturers. They get rich.
ALBERT: I think it's more a kind of fever. Nobody wants it in particular and then, all at once, here it is. We didn't want it. The English didn't want it. And here we are fighting.
The characters are considering possible origins for the war, and in doing so, potential origins for the chauvinism consuming their country. The first is that the chauvinism was manufactured so various people and organizations could profit. The second is that chauvinism is a type of thought virus, spread from one person to another like the flu.
PAUL: It isn't customary to ask for salutes here. But I'll tell you what we'll do. We're going to attack a town that we tried to take once before. Many killed and many wounded. It was great fun. This time you're going with us. If any of us stops a bullet, before we die, we're going to come to you, click our heels together and ask stiffly, "Please, Sergeant Himmelstoss, may we go?"
The treatment of Himmelstoss shows us how much Paul and his friends have changed since the film's opening. In Kantorek's class, they were all about the grand adventure and dying for the fatherland. But if we see Himmelstoss as representing militarism and nationalism, then Paul's disregard for his authority demonstrates that his chauvinistic ideals are gone.
GENTLEMAN 1: I'm glad to know you, young man, I'm glad to know you. And how are things out there? Terrible, eh? Terrible. But we must carry on. After all, you do at least get decent food out there. Naturally, it's worse here. Naturally. But the best for our soldiers all the time. That's our motto: the best for our soldiers.
ALL: The best for our soldiers.
GENTLEMAN 1: But you must give the Frenchies a good licking! And if you boys want to come home, let me show you what you must do before you can come home. Give us a hand there, men.
Paul and his fellow soldiers may have lost their chauvinist zeal, but that's not true of the people of his hometown. Without experience the atrocities of the Front firsthand, Paul's father and his entourage remain ignorant of the realities of the war. As such, they still treat it like a giant game. And like all fathers who bust out Risk on family game night, they're totally unaware they are the only ones enjoying the game.
KANTOREK: From the farms they have gone, from the schools, from the factories. They have gone bravely, nobly, ever forward, realizing that there is no other duty now but to save the fatherland. Paul! How are you, Paul?
PAUL: Glad to see you, Professor.
And he's still at it. One of the hallmarks of chauvinism is that it is based on belief, faith, and emotions, not facts and reason. By this time, Kantorek knows the war was not quick, the losses were not few, and the suffering at the Front has been immense. But because his chauvinism was based on a belief of his own country's superiority, no facts will ever change his mind.
TJADEN: He got homesick. You remember about the cherry blossoms?
TJADEN: I guess he never got over that. He started out one night to go home and help his wife with the farm. They got him behind the lines and we never heard of him since. He was just homesick but probably they couldn't see it that way.
Earlier, we saw Detering's pain at being away from his farm and his wife. He simply wanted to return to them, and anyone who has ever been homesick can empathize with him. But the military officials don't see the individual's plight, only the plight of the nation and the military. As such, they see the act as desertion, and it is strongly implied the punishment will be execution.