> It also probably goes with the fact that it is a very big country sharing one culture
Some Americans, even here on HN, genuinely believe that different states have different cultures in the same way different countries in Europe have different cultures cultures.
Sure, it's not incompatible. There is a European culture, it's just a question of granularity. And there are subcultures in countries (some countries are even divided between different languages).
Still, Americans from everywhere in the US have this tendency to genuinely believe that the whole world believes the US are the best country in the world. That seems like a cultural trait in the US.
Some Americans, even here on HN, genuinely believe that different states have different cultures in the same way different countries in Europe have different cultures cultures.