Every Chinese engineer I work with knows how to measure in li, fen, & jin; the Japanese measure floor area in tatami, etc. I think you're conflating customary u

Every Chinese engineer I work with knows how to measure in li, fen, & jin; the Japanese measure floor area in tatami, etc. I think you're conflating customary units with scientific units. Most of the world uses local, customary, units. The US — like most of the world — uses metric for science stuff.