@mattbrowne – I’m not sure that it’s fair to blame only the republicans, much as I would like to.
Moving from our inches/feet to the metric system is not something that happens overnight. It is at least a single generation, and probably multiple generations, to re-educate and re-acclimate every living person in the US to a new system. That’s 300,000,000 million people that have been raised with one system and would need to change how they think of things.
And to what tangible benefit?
Other than the “we’ll be like every country in the rest of the world” argument, which is, frankly, not compelling, where is the benefit to Mr. or Mrs. America? Yes, there might be a couple of jobs gained or lost, and manufacturers might save a couple of dollars on packaging, but how does the average guy on the street benefit? The answer is – they don’t. Moving to metric in the US does not improve the life of the average person.
And by the way, the Picard argument is also not compelling.