And this concern about “who and how many” is well founded. Alexander Hamilton himself noted the dangers of cultural division from immigration. https://www.iwp.edu/articles/2016/12/21/hamiltons-actual-vie.... He wrote: “The safety of a republic depends essentially on the energy of a common national sentiment; on a uniformity of principles and habits; on the exemption of the citizens from foreign bias, and prejudice; and on that love of country which will almost invariably be found to be closely connected with birth, education, and family.”
Silicon Valley understands that culture drives outcomes when it comes to companies and startups, but have a huge blind spot about culture when it comes to countries. But culture matters just as much for countries as companies. Immigrants bring their cultures with them—typically from places less successful than the U.S.—and that culture persists for generations: https://www.sup.org/books/economics-and-finance/culture-tran.... That has serious consequences for society. You can easily look at Minnesota versus New Jersey and see that immigration patterns have left an imprint on culture centuries later. And it’s equally clear that certain parts of the country are culturally better than other parts of the country. America would be much more orderly and well governed if more of it was like Minnesota and Utah and less like West Virginia or New Jersey.