Why in the world would one country decide to use a system of measurement that is different from every other nation? This question has plagued me for years and in economic terms the cost to switch over is not as horrible as I think the U.S. population is lead to believe. It makes sense to have units of measure to be in tens. We have ten toes and ten fingers. Why 12? While there would be a cost up front to change all the highway signs and such to metric, in the long run the United States would be better off when it comes to tools, import cars, importing weighed goods, etc. It would not take very long for the population to get use to the new measurement system, after all, anyone who immigrates to the U.S., they have to learn our system of measurement. It is more cost effective for me as a consumer to have one set of tools in metric measurement than metric and standard. I have magnets on my refrigerator that give me the measurement conversion for cooking. It doesn’t take long to learn those conversions just from a cooks’ stand point. All vehicles have kilometers on the speedometer. The word speedometer references to the metric system all on its own. Why not just switch over and be done with it. Of course there would be some time lag when it comes to American made good that use units of measurement in the U.S. standard that would have to switch over to metric, but overall I believe that the switch would benefit future generations.
You bring up a good idea to think about. America is technically still the most dominate country, and has been for many years. We are known for innovation, success, and have been the power player since we were founded by out great fathers. The start of America using the standard measuring system began with the British Empire; they were using this system and America didn’t want to change to a less-complicated version for fear of a costly delegation to France (http://science.howstuffworks.com/why-us-not-on-metric-system1.htm). As the years went on and the United States being a leader in the top nations, the US tried to implement the metric system into schools, industries, manufacturing facilities and so on, but it was never entirely successful.
So after using the standard measuring system for so long in the US, I think we have just dig ourselves in a large hole. You mentioned it would be easy to switch over, but I think it would be too costly to adopt the metric system. I also think that individuals, businesses, and the government would not be open to switching. This is a point because Congress made it a voluntary decision for all 50 states to adopt the metric system, and not one state has yet.