Even in absolute numbers, total immigration is nowhere near its volume in those years when U. S. population was less than half of what it now is. Rather, it is a country of the descendants of immigrants. Natural resources and the environment are not at risk from immigration. The long-term trends reveal that our air and water are getting cleaner rather than dirtier, and our supplies of natural resources are becoming more available rather than exhausted, contrary to common belief. Immigration increases the technical knowledge which speeds these benign trends.
Immigrants increase the flexibility of the economy.
Newcomers are unusually mobile both geographically and occupationally. Hence they mitigate the tight labor markets that the U. S. is beginning to experience. Immigration reduces the uncuttable social costs of the elderly. More and more of the U. S. population is retired, with a smaller proportion of adults in the labor force. New immigrants typically are just entering the prime of their work lives and tax-paying years.