https://uscode.house.gov/view.xhtml;jsessionid=8314B6B7A95CC...
As you mentioned, the foot and all other U.S. customary units are based on the International System of Units (SI).
It seems that the US, Myanmar and Liberia, the current users of the imperial system, could join us with minimal or negligible cost.
Nitpick: That's wrong. Neither the US, nor Myanmar use the imperial system.
The US uses US customary units, while Myanmar uses traditional Burmese units of measurement. Neither of which are imperial units (as defined by the British Weights and Measures Act) and only US customary units are related to the imperial unit system.
eg: imagine you have a 5 & 1/2 foot cabinet with 4 equal sections framed out with 3/4" boards, what is the height of each section? It's (5 & 1/2' - (5 * 3/4")) / 4 which I guarantee nobody is working out in their head easily.
Decimal system isn’t our finest legacy. If we had to go back in time, we’d change history by choosing duodecimal system from the get go.
Metric rulers just don't use those because there is tradition of using different fractions. In metric you typically use: 1, 3/4, 6/8, 5/8, 1/2, 3/8,1/4, 1/5, 1/8, 1/10, 1/20, 1/25, 1/50, 1/100...
People go the other way too--some American machinists work in 'mils' (=1/1000 of an inch), since one often wants (and can achieve) that kind of precision.
We could pass a law saying "we're metric now", but it would likely just be a formality while we continue using Imperial.
Humorous view on the situation: https://www.youtube.com/watch?v=hid7EJkwDNk