Last month, New Mexico’s governor announced that the state would soon become the first in the country to offer universal free child care. This was a momentous development for child-care proponents such as myself, who have long argued that wide-reaching free programs are crucial for parents and for a healthy democracy. Notably, the policy frames child care not as a private service but as necessary social infrastructure—the kind that, like schools and roads and libraries, should be publicly funded and available to everyone, regardless of their income.

Since the announcement, advocates and pundits have been unreserved in their excitement: An article in Bloomberg declared this was proof that “Universal Child Care Doesn’t Have to Be a Fantasy.” A writer for The Nation made the case that other states should establish similar programs. But this victory lap may be premature. New Mexico has many hurdles to overcome before anyone can declare the policy a success—and the state could, after all of this attention, fail to fully deliver on its promise.

Although the universal policy will not take effect until Saturday, New Mexico already has, at least in name, one of the most comprehensive child-care funding programs in the United States. Its current system, which offers free care to families with children ages six weeks to 13 years, does have an income-based cutoff, but it’s a generous one, in effect meaning