Marxism and the USA's fair to middling. I enjoyed looking at US history through a Marxist lens. But to use the word "communist" in connection with Native American civilization and the early Jesus movement? Not so much. Sure, elements of each would make Lenin and other communist leaders and theorists smile, but I'm always hesitant to take a term from the modern world and ascribe it to communities from the past.
For a life-changing introduction to the prevalence of class struggle throughout the nation's existence, pick up a copy of Howard Zinn's [b:A People's History of the United States: 1492 to Present|2767|A People's History of the United States 1492 to Present|Howard Zinn|http://d.gr-assets.com/books/1348900509s/2767.jpg|2185591]. And if graphic novels float your boat, try [b:A People's History of American Empire|1782543|A People's History of American Empire|Howard Zinn|http://d.gr-assets.com/books/1312042463s/1782543.jpg|1781392]. You won't regret it!