But the bitterly negotiated budget agreements between Obama and the Republican majority that seized the House in 2010 reversed this growth. Those fiscal deals focused on cutting discretionary spending, which funds most investments in future generations, while largely exempting the entitlement programs that mostly benefit the elderly, including Social Security and Medicare. Need-based programs that benefit kids, such as food assistance, also spent less as the economy recovered. By 2017, the Urban Institute reports, spending on kids had slipped back to 9.4 percent of the federal budget.

Now all of the trend lines are pointing down for kids. The Urban Institute forecasts that spending on children will fall below 7 percent of the federal budget by 2028. Over the next decade, it estimates that total federal spending, in dollars adjusted for inflation, will increase by about $1.6 trillion, but that programs for kids will receive only 1 percent of that massive flow.

Spending on kids is being squeezed primarily by two other rapidly growing categories—both of which represent an obligation to the past. The first is the portion of Social Security, Medicare, and Medicaid targeted to adults. Those programs represented about 30 percent of federal spending in 1990, but they have soared to 45 percent of the federal budget today. Washington now spends almost six times as much for every senior as it spends on each kid. Over the next decade, that disparity is unlikely to improve: The Urban Institute projects that the adult portion of the big three entitlements will consume more than three-fifths of all new federal spending. By 2028, for the first time, the adult share of those programs will constitute fully half of the federal budget.

The other rapidly growing source of federal spending is interest on the federal debt. By all projections, the huge tax cuts passed last year by Trump and the Republican Congress—which primarily benefit top earners, who are themselves clustered in older generations—will vastly enlarge the federal debt that younger generations must shoulder in the decades ahead. Increased interest costs are expected to consume a daunting 30 percent of all new federal spending through 2028. By contrast, defense, like kids’ programs, is expected to command only about 1 percent of those increased outlays.

Julia Isaacs, an Urban Institute senior fellow and a co-author of the study, notes that the tax cut undermines younger generations from two directions. “It’s like a double whammy,” she told me. “We are not spending very much [on them] today and we are unable to raise revenues to pay for what we are spending, [so] we are also leaving them a debt, which they will be paying off.”

All of these fiscal choices have stark racial implications. Whites now comprise more than three-fourths of the senior population, according to calculations by William Frey, a Brookings Institution demographer. That number is projected to decline only slowly in the coming decades. By contrast, as Frey reported in a recent study, kids of color already represent a majority of the population aged 9 and under, and are expected to compose a majority of all Americans under 18 by 2020.