According to recent UN reports, the United States is one of the countries with the most amount of resident immigrants [0]. In fact, according to their report, a whole 20% of immigrants (defined as people living somewhere they weren't born) call the US their home.
Another problem with your argument is that the relationship between more thorough screening of immigration applicants and a country's "level of isolationism" is lacking evidence. Perhaps a country's capabilities in screening applicants is simply correlated to how many people are trying to immigrate there? Just a hypothesis based on the data linked above.
But if I may counter your anecdote with my own: I am an immigrant in the US (Bay Area) and so are all my friends. Actually I think I interact with less than a handful of Americans regularly, everyone else is Mexican, Chinese, Slovenian, Indian, Ukranian, etc. I'm happy to have had the opportunity to find a home and work here, and I think so are they.
Another problem with your argument is that the relationship between more thorough screening of immigration applicants and a country's "level of isolationism" is lacking evidence. Perhaps a country's capabilities in screening applicants is simply correlated to how many people are trying to immigrate there? Just a hypothesis based on the data linked above.
But if I may counter your anecdote with my own: I am an immigrant in the US (Bay Area) and so are all my friends. Actually I think I interact with less than a handful of Americans regularly, everyone else is Mexican, Chinese, Slovenian, Indian, Ukranian, etc. I'm happy to have had the opportunity to find a home and work here, and I think so are they.
[0] https://www.un.org/en/development/desa/population/migration/...