I am interested in the population problems in Japan, and to a lesser extent South Korea. Both strongly disfavor immigration, and their reproduction rates are not keeping up. Some cities are losing population fairly rapidly, not because folks are moving elsewhere. The US needs immigrants. The A bomb would not have been possible without them, I suspect.
The simple question is not whether we should accept immigrants but how, in some fairly orderly manner or just take whoever shows up to live in some underground kind of existence here for the rest of their lives.