What is the theme in Barrio Boy by Ernesto Galarza?

One of the novel's main themes is that of industrialization, specifically the arrival of rail lines (train lines). Over the course of the novel, we see how this technology changes the lives of the Galarza family in numerous ways. These changes include the opportunity for employment and travel, which are both positives, but also the quick moving transport of the revolutionaries.... a definite negative. The more the Galarzas try to escape the war, the closer it follows them.