While more can always be said, I do have some discussion of this when I wrote about "The American Way" in regards to Superman last year:

The 1950's television program "The Adventures of Superman" introduces Superman as fighting a "never ending battle for truth, justice, and the American Way." What exactly was "the American way," in the minds of the writers of the series and their intended audience?

Particular relevant is the 1924 quote:

And what is the "American Way"? It can be summed up in two words -- voluntary cooperation. This means that a free people has learned how to work together and to work successfully, without surrendering the individual freedom of its members. It means that the government exists for the citizen, not the citizen for the government; that an American is free to choose his own work and is protected in the enjoyment of the fruits of his labor.

Note that absolute self-sufficiency is not quite the same thing -- there is still the sense of helping community in individualism, it is just cojoined with a freedom to choose.