One of the major reasons white non-college voters turned to Donald Trump in 2016 and 2020 is the fear of lost white hegemony — that the United States will become a majority-minority nation sometime in the near future.

Almost simultaneously, however, the decisively majority-minority work force will be providing the bulk of the revenue going toward Social Security and Medicare.

In other words, the payroll taxes collected from a majority-minority population will be sustaining the white working-class men and women who are still alive by midcentury, dependent on those two programs for half their retirement income and for a large share of their medical costs.

The evolving role of minority groups in the domestic economy is just one example of the profound role births, deaths and rates of immigration play in shaping the balance of power between red and blue America.

The most important shift here and in other developed countries is the steady decline in the number of prime-age workers (from 18 to 64) and the steady growth of the retirement-age population (65 and older).

“U.S. births have fallen steadily since 2007,” Melissa Kearney and Phillip Levine, economists at the University of Maryland and Wellesley, wrote in “The Causes and Consequences of Declining U.S. Fertility,” “and the total fertility rate is now well below replacement level — the rate at which the population replaces itself from one generation to the next.”