AS PRESIDENT DONALD TRUMP attempts to reduce immigration into America, new research suggests how rapidly that strategy is likely to disadvantage many of his most loyal supporters. In 2016, there were more deaths than births among America’s non-Latino white population. The future quality of life of this aging, shrinking population increasingly depends on two factors: sustained high fertility amongst minority groups already in the country—and continued immigration.

Rogelio Sáenz of the University of Texas and Kenneth M. Johnson at the University of New Hampshire used data from the National Centre for Health Statistics of the Centre for Disease Control to find that deaths amongst non-Latino whites surpassed births in the same group for the first time in history two years ago. The white non-Latino population declined in 26 states in 2016, up from four states in 2004. Declining fertility and rising mortality both played a role: between 1999 and 2016, the number of non-Latino white births fell by 11%—with a particularly rapid decline during the financial crisis—while the number of deaths rose by 9%.

The trends are unlikely to reverse much: every year, there are fewer white non-Latino women of child-bearing age and more white old men and women. The median age of this demographic group has risen from 39 in 2000 to 43 in 2016.

The researchers’ work suggests that recent Census Bureau forecasts for white non-Latino population size are probably biased upward. But even those forecasts suggested that in 2020 there would be 70,000 fewer births than deaths among that population group, with its overall size only sustained in that year by migration. And even accounting for migration, the forecasts predict the white non-Latino population will fall by about a quarter of a million people each year by 2030 and nearly three quarters of a million a year by 2050.

Minorities and migrants are filling the gap. Across America, there were 4.9 Latino births for every Latino death and 1.7 African American births for every death in that demographic group. And even allowing for higher natural population increases amongst minority groups, Census Bureau forecasts suggest that without migration and births to foreign-born mothers, the American population as a whole would decline by about 6m in the period between 2014 and 2060. Migrants are a particularly important factor in sustaining the size of America’s workforce: in 2014, 80% of foreign-born inhabitants were aged 18 to 64 compared to 60% of those native born.

White Americans should be reassured by that. Under current Census Bureau projections, they will account for less than half of the total population within the next three decades: 48% by 2050. But they will make up 60% of the population aged 65 or older. The elderly work at considerably lower rates and rely on public support for health care and welfare payments at far higher rates. That means than non-Latino whites would be particularly at risk from the economic stagnation and budget constraints associated with a declining workforce that would result from lower minority birth rates or harsher limits on immigration.

The political implications of demographic change are not clear. Given growing inter-marriage rates and other signs of assimilation, as well as evidence of declining racism in the country as a whole, the stark ethnic and cultural categorisations used by the Census Bureau are likely to have less relevance over time.

And political allegiances amongst minority groups may evolve. Many Latinos are culturally conservative. Republicans, including former president George W. Bush (who carried 44% of the Latino vote in 2004) and Senator Marco Rubio of Florida have advocated reaching out to Latinos as a source of future political strength for the party.

Unsurprisingly, at the moment, such a political realignment appears rather a distant prospect.