Antonio Storcke comments

It has to do with politics. Starting back with President Thomas Jefferson, who wanted to go metric. Jefferson was waiting to receive the prototype Kilogram and prototype Kilometer so he could test it. Unfortunately, due to pirates, he never received it. The impetus to investigate and implement a metric conversion left as administrations changed. President Gerald Ford tried to implement it, but at that point it was seen as too expensive to implement as the sole standard in the USA. There was a Presidential candidate (Lincoln Chafee) who wanted to do it but his desire was colored by the media as eccentricity and he was embarrassed by it. At this point, the US has adopted the Metric system in everything but Road signs , the Gas pump, and day-to-day cooking, measurements for clothing, and lumber. These are very important and must be addressed in offer for a full conversion to metric. Household cooking is meant to be imprecise so traditional imperial measurements mill likely remain in that category. What we are seeing in the USA amounts to a gradual metric conversion.