Yes first or second generation Americans (or long established Americans) don’t owe anyone else any responsibility. They only owe their descendants and fellow Americans here. They don’t owe non descendants elsewhere anything. It’s not like they can go back to their grandparents country and say hey, remember my grandparents, they were from here, I need help, help me out over here!
> It’s not like they can go back to their grandparents country and say hey, remember my grandparents, they were from here, I need help, help me out over here!
That's not entirely true everywhere though. For example, I was born in the US, as were my parents and grandparents. My great-grandparents immigrated from Italy, and if I can gather the proper documentation, I'm eligible for Italian citizenship. If I ever get this done, then yes, I could indeed go back to my great-grandparents' country and do what you suggest is silly. I believe quite a few other countries also have policies like this.
