Meanwhile, what of the misery and damage on which this glut of cheap clothing is founded?

Surely you mean the hundreds of millions of Chinese and Indians that have 'been lifted out of poverty'?

Cheap clothing is leading people to treat clothes in a qualitatively different way. Clothes are becoming throwaway consumption items.

Imports now make up more than half of the value of the domestic market in apparel in the US, and that means over 75% of the volume. I'd doubt that factors like 'higher mechanisation' and 'lower domestic wages' figure into the equation of lower prices as more than mere statistical blips.