US is not a "natural" country, it is a colony and the ~350 million population are not Americans, they are immigrants who call themselves American. This is why they usually identify as Something-American like Irish-American, African-American, and so on. Something that is not true in a real country like Germany. Which is why "nationalism" has a different meaning too and could lead to "Reich" in Germany but not in the US.
That's right, nationalism can't exist in the USA because it's a country of European migrants. I have some friends and relatives who life in different countries. I've heard from everyone that in the USA and Canada, you feel like a local if you manage to integrate well within the country and the society but in European countries, you are still a foreigner, doesn't matter how much you try to integrate with their culture.
Btw I believe that there is an attempt to destroy nationalism in European countries like the UK, Germany, France and others. When I was in France, it was full of black people. I know from history that the French people are white. When there is such a mixture of people and also a huge promotion of acceptance of every religion and race, then such a country can't be nationalistic.
"land of opportunity" something that was always a lie
I hear from many local people, who are in the USA that it's really a land of opportunity. Why do you think that it's a lie? I've never been in the USA, so I can't really talk but people around me say otherwise. We have a very good example, who is a UFC fighter, from a very poor family and village, who moved to the USA, worked on construction and today is a UFC fighter. I'm talking about Merab Dvalishvili.