I still recall a movement back in the 60s to switch the US to the metric system. In 1968, Congress authorized the U.S. Metric Study, a three-year study of systems of measurement in the U.S., with emphasis on the feasibility of metrication. The United States Department of Commerce conducted the study. A 45-member advisory panel consulted and took testimony from hundreds of consumers, business organizations, labor groups, manufacturers, and state and local officials. The final report of the study concluded that the U.S. would eventually join the rest of the world in the use of the metric system of measurement.
Up until then, soft drinks like soda, etc. were sold in 1/2 gallon size. It took a while to adjust to the metric sized bottles. It's still odd that soft drinks follow the metric system while milk continues to be sold by the gallon.
The problem is, people have choices! ;’) If the metric system were required everywhere, and the old system deprecated, racist gun-clinging xenophobes wouldn’t be preventing gay marriage or conducting the war on women, the war on drugs, or the war on undocumented Americans.