The US is inching towards becoming metric...
You have always had 'metric' decimal money, car-engines' are measured in 'cc' [cubic-cms], the military measure horizontal distances in 'meters' [but vertical in 'feet' like all international aircraft!], and you buy cola/juice it's in 'liters' and wine is bottle in metric sizes, nutrition values on food labeling are all in metric units, photography is metric [35mm etc], even bullets come in metric sizes...
http://www.youtube.com/watch?v=2UmFCc4TOTY