What is the theme in Life on the Mississippi by Mark Twain?

One of the most prevalent themes in Life on the Mississippi is the growth of America as a country, as well as the development of national and regional characteristics. Through the rise and fall of the steamship industry, Twain traces the development of a certain area of the United States. Thus, he begins his story by telling of the discovery of the Mississippi and of its early uses before giving the narrative its more personal tone. Here, we begin by seeing the Mississippi as an undiscovered resource, to be followed by a discussion of its uses for the growth of industry, as well as its mythical character in Twain's eyes.