Foreign trade is, interestingly enough, considered the most important reason to convert the US to the metric system: https://en.wikipedia.org/wiki/Metrication_i

Foreign trade is, interestingly enough, considered the most important reason to convert the US to the metric system: https://en.wikipedia.org/wiki/Metrication_in_the_United_States#20th_century https://en.wikipedia.org/wiki/Metrication_in_the_United_Stat... Apart from trade though, this issue might cause some countries to hesitate to work with the US for scientific research or related initiatives: https://en.wikipedia.org/wiki/Mars_Climate_Orbiter#Cause_of_failure https://en.wikipedia.org/wiki/Mars_Climate_Orbiter#Cause_of_...