A curious hypothetical from David Bernstein:

Imagine, for example, if the ghost of Justice William Day, author of Hammer v. Dagenhart, rose from the grave and showed up at Dahlia Lithwick’s door, ready for an interview. Lithwick, in her most outraged tone of voice, asks, “How could you and your colleagues invalidate laws aimed at the odious practice of child labor?” Would Day be out of line in responding, “We were following our best understanding of the Constitution’s limits on federal power, and anyway it didn’t seem to us that impoverished Mississippi needed the same rules as New York with three times the per capita income. But let me ask you something: is it true that even though there are no longer any constitutional restrictions on federal power to regulate labor, and that the U.S. is now wealthy beyond anything we could have dreamed of in the 1910s, that you still allow kids under sixteen year olds to engage in dangerous farm work?”

For some reason I am thinking of the dream sequence from Fiddler on the Roof.