The Burr Under America's Saddle

Robert Penn Warren got it right a while back in an interview Paris Review now has online:

INTERVIEWER: Do you feel that there are certain themes which are basic to the American experience, even though a body of writing in a given period might ignore or evade them?

WARREN: First thing, without being systematic, what comes to mind without running off a week and praying about it, would be that America was based on a big promisea great big one: the Declaration of Independence. When you have to live with that in the house, that’s quite a problemparticularly when you’ve got to make money and get ahead, open world markets, do all the things you have to, raise your children, and so forth. America is stuck with its self-definition put on paper in 1776, and that was just like putting a burr under the metaphysical saddle of Americayou see, that saddle’s going to jump now and then and it pricks.