There are some things that America does REALLY right. However, a lot of them are stuff we only do in theory. Our dedication to personal freedom is abridged constantly. We are all about limited government, but let them control all sorts of things they shouldn't and get away with things they shouldn't be allowed to do. (Guess who got frisked in an airport this weekend?) We also only halfheartedly pursue equality and equal justice for all. We do all these things, and we care passionately about them, in at least a theoretical sense. But we don't work nearly as hard as we could on them.
So yeah, America is pretty exceptional, but we have a looooooooooong way still to go.