What is the theme in American Pastoral by Philip Roth?

Chaos is a central theme in this book. Roth may have been before his time in writing about chaos. The solid, upstanding life lived by Swede's parents dissolves into total chaos in Swede's life, almost like a chain reaction after Merry bombs the store. In the end, no matter how much effort goes into keeping things orderly and upright, chaos eventually overtakes everything.