Why did Caputo join the Marines? What did he hoping would happen to him as a soldier?

Caputo enlists in the Marines in the hopes to end his dreary days of comfortable living in the small mid-western suburban town of Westchester, Illinois. He enters the war with romantic notions of being a hero, with thoughts of ending the war within a few short weeks or months and returning home to a parade of patriotic countrymen that will slap him on the back and ask him to tell them another heroic tale of his adventures in Vietnam.