From my perspective as a Canadian, the traditional philosophy of being an American is having the freedom to control the course of your own life. Basically "freedom" and "liberty" is the foundation of this philosophy.
Obviously this philosophy has been extremely successful judging by the power that America now wields in the world. To me, it's this power that could lead to it's downfall. It seems to me that America, or at least it's government is using this power to try to force the rest of the world into adopting it's own philosophy and thus creating a backlash from some people.
I wonder if the regular Joe American who considers his freedom to be so important really thinks his neighbour in the Army should be overseas installing American approved governments in countries he knows nothing about. I would say he's probably more concerned about making a better life for his kids, getting a good job or running his own business and doing it the way he wants to do it.