I think there is some truth in that, but I don't believe it's the whole truth.
America is the great melting pot of human existence. Every problem the world has ever seen with Idealism, Zealotry, and fanatical belief, America deals with in spades.
Yes, we are arrogant and quick to abandon our principles in favor of Idealism, and belief. Why should that be a surprise? That seems to be nothing more than human nature at work.
The thing that I believe gets overlooked is the principle at the base of the great American experiment.
I consider myself an American in every sense of the word. my principles are the product of American society.
My loyalties are thus, my family, my circle of friends, my community, my state, my country, my species, in exactly that order, any Ideals and subsequent beliefs all come second to that principle.
Granted, I am far from perfect but my ducks are all in a row underneath it all.
I don't see anyone else out there doing any better, so all the stone throwing at America is nothing more than the pot calling the kettle black.
If there is any people on this planet not struggling to uphold this principle against Idealism, I am not aware of it at this time.