From The New York Times:

Obscured by other parts of President Biden’s $1.9 trillion stimulus package, which won Senate approval on Saturday, the child benefit has the makings of a policy revolution. Though framed in technocratic terms as an expansion of an existing tax credit, it is essentially a guaranteed income for families with children, akin to children’s allowances that are common in other rich countries.

The plan establishes the benefit for a single year. But if it becomes permanent, as Democrats intend, it will greatly enlarge the safety net for the poor and the middle class at a time when the volatile modern economy often leaves families moving between those groups. More than 93 percent of children — 69 million — would receive benefits under the plan, at a one-year cost of more than $100 billion.

The bill, which is likely to . . . be signed by Mr. Biden this week, raises the maximum benefit most families will receive by up to 80 percent per child and extends it to millions of families whose earnings are too low to fully qualify under existing law. Currently, a quarter of children get a partial benefit, and the poorest 10 percent get nothing.

While the current program distributes the money annually, as a tax reduction to families with income tax liability or a check to those too poor to owe income taxes, the new program would send both groups monthly checks to provide a more stable cash flow.

By the standards of previous aid debates, opposition has been surprisingly muted. While the bill has not won any Republican votes, critics have largely focused on other elements of the rescue package. . . . Senator Mitt Romney, Republican of Utah, has proposed a child benefit that is even larger, though it would be financed through other safety net cuts.

While the proposal took center stage in response to the pandemic, supporters have spent decades developing the case for a children’s income guarantee. Their arguments gained traction as science established the long-term consequences of deprivation in children’s early years, and as rising inequality undercut the idea that everyone had a fair shot at a better life. . . .

Mr. Biden’s embrace of the subsidies is a leftward shift for a Democratic Party that made deep cuts in cash aid in the 1990s under the theme of “ending welfare.” As a senator, Mr. Biden supported the 1996 welfare restrictions, and as recently as August his campaign was noncommittal about the child benefit.

The president now promotes projections that the monthly checks — up to $300 for young children and $250 for those over 5 — would cut child poverty by 45 percent, and by more than 50 percent among Black families.

“The moment has found us,” said Representative Rosa DeLauro, a Connecticut Democrat who has proposed a child allowance in 10 consecutive Congresses and describes it as a children’s version of Social Security. “The crystallization of the child tax credit and what it can do to lift children and families out of poverty is extraordinary. We’ve been talking about this for years.”

The campaign for child benefits is at least a half-century old and rests on a twofold idea: Children are expensive, and society shares an interest in seeing them thrive. At least 17 wealthy countries subsidize child-rearing for much of the population, with Canada offering up to $4,800 per child each year. But until recently, a broad allowance seemed unlikely in the United States, where policy was more likely to reflect a faith that opportunity was abundant and a belief that aid sapped initiative.

It was a Democratic president, Bill Clinton, who abolished the entitlement to cash aid for poor families with children. The landmark law he signed in 1996 created time limits and work requirements and caused an exodus from the rolls. Spending on the poor continued to grow but targeted low-wage workers, with little protection for those who failed to find or keep jobs.

In a 2018 analysis of federal spending on children, the economists Hilary W. Hoynes and Diane Whitmore Schanzenbach found that virtually all the increases since 1990 went to “families with earnings” and those “above the poverty line.”

But rising inequality and the focus on early childhood brought broader subsidies a new look. A landmark study in 2019 by the National Academies of Sciences, Engineering and Medicine showed that even short stints in poverty could cause lasting harm, leaving children with less education, lower adult earnings and worse adult health. Though welfare critics said aid caused harm, the panel found that “poverty itself causes negative child outcomes” and that income subsidies “have been shown to improve child well-being”. . .

Under Mr. Biden’s plan, a nonworking mother with three young children could receive $10,800 a year, plus food stamps and Medicaid . . . Full benefits extend to single parents with incomes of $112,500 and couples with $150,000.

. . . Samuel Hammond, a proponent of child allowances at the center-right Niskanen Center, said the politics of aid had changed in ways that softened conservative resistance.

A quarter-century ago, debate focused on an urban underclass whose problems seemed to set them apart from a generally prospering society. They were disproportionately Black and Latino and mostly represented by Democrats. Now, insecurity has traveled up the economic ladder to a broader working class with similar problems, like underemployment, marital dissolution and drugs. Often white and rural, many are voters whom Republicans hope to court. . . .