Before we bite the hand that feeds us, let us remember how much of the old-world charm and plain good sense of the United States derives from the fact that it skipped the 19th century.
You can see this in the formal manners, the widespread look of puzzlement at the mention of Darwin, and the obviously 18th century banknotes.
In fact it is not widely appreciated that having made such an extraordinary success of the 18th century, bringing forth a new nation, conceived in Liberty, and dedicated to the proposition that all men are created equal, the US decided to extend that century by over a 100 years, skipping the 19c (and the development of the metric system) altogether.
The US was, of course, tragically dragged into the 20c by the First World War, but took some time to grasp the full implications of that strange and terrible century, and thus managed not only avoid its worst excesses, but actually to provide a new home to many of its casualties.
In my view we should all be profoundly grateful for this unusual historical path, and the fossilised preservation of an imperial system of measurement seems a very small price to pay for it (even if it does produce the occasional
technical glitch).
Nor should we exaggerate the uniqueness of the US in this respect. There are two other notable beacons of resistance to an international system of measurement:
http://en.wikipedia.org/wiki/File:Non-Metric_User.svg
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