What is the theme in Hell's Angels: A Strange and Terrible Saga by Hunter S. Thompson?

The text is fundamentally a book-length journalistic report about the Hell's Angels, a motorcycle outlaw gang. The overarching theme of the book is the culture and priorities of motorcycle gangs. The text seeks to answer basic questions by examining the origins of the motorcycle outlaw culture: their development over a period of perhaps twenty years; their goals, aims, and activities; and their significance in a larger social context. The Hell's Angels are the specific focus of the text; but various other motorcycle gangs are mentioned, and some detail on several other gangs is provided. The Hell's Angels' particulars are noted so that they can be isolated from the larger phenomenon.