[lq9AJ8yrfs]

> There’s a positive externality of readily available childcare: one adult to many children is more efficient than home care,

An externality [1] happens when there is some additional uncaptured aspect of a transaction, a "missing market". It seems implausible that there is a missing market in child care-- there are plenty of choices out there, different service levels and pricing. And when you put your child into child care and are now freed of child care responsibility for working hours, you can directly participate in the labor market, right?

Instead of externality maybe you could support intervention instead by arguing that there are facets of the child-care market that you don't like, resulting in the observed market outcome, such as capital overheads, barriers to entry, transportation barriers, or regulation.

[1]https://en.wikipedia.org/wiki/Externality