In All Quiet on the Western Front, why did the boys enlist in the army?

In All Quiet on the Western Front, Paul suggests that social pressure was one of the reasons the boys enlisted in the army.

Paul identifies one potential reason why the boys enlisted in the book's first chapter. When one mentions that "Kantorek sends his best" to the soldiers, it triggers a reflective moment. Paul discusses how one of the boys' teachers named Kantorek had encouraged them to enlist in the army. They had to endure "long lectures" from Kantorek about how it was their duty to enlist. Paul says that the old teacher "used to glare at us through his spectacles and say in a moving voice: 'Won't you join up, Comrades?'" Kantorek called the boys who served "The Iron Youth." Paul's story explains how many of the young men enlisted because they were compelled to do so. They were told that volunteering for service was their patriotic duty and that the country's need justified their sacrifice. These elderly people depicted the war as nobly grand, and something that young people should eagerly embrace.

Paul has been on the front lines long enough to view such advice in a skeptical light. As he reflects on Kantorek, Paul remarks how "These teachers always carry their feelings ready in their waistcoat pockets, and trot them out by the hour. But we didn't think of that then." Paul is direct in his suggestion that the people who were encouraging boys to fight at the front did not have to endure it themselves. At the end of the chapter, Paul's bitterness at this reality is clear:

Yes, that's the way they think, these hundred thousand Kantoreks! Iron Youth. Youth! We are none of us more than twenty years old. But young? Youth? That is long ago. We are old folk.

The "hundred thousand Kantoreks" sold the idea of enlisting for the war to naive young men. Paul suggests that war removes the innocence from the young. The experiences of being deceived into enlisting for the war has made them "old folk."