I don't know if people are old enough to remember this. Back in the 70s, they really made a push in the US to convert the road signs to metric. From time to time they have tried, and people have always resisted. Anyway, in the 70s they studied it, made a commission (which in the end Ronald Reagan destroyed as he did so many other things), and tried again. They started putting sneaky little kilometer signs underneath the mph and "mile 5" and whatever markers, just to get people used to the idea. (They are still around, in some places.)

Nope. People could see where it was going. America as does some other countries has a proud tradition of shooting holes in road signs with guns. I don't know why people do this, but when the metric signs came along they shot the shit out of them. I don't know that the unsustainability of keeping them installed when people kept shooting them into semi-oblivion was part of what made them abandon the idea, but it certainly couldn't have been good for the morale of the people working on it, and probably it made a difference.

That is all the good and all the bad of America rolled up into one. The people had spoken. Keep your god damned kilometers. We're not changing the date for Thanksgiving. It's not the Gulf of America. Fuck you, I won't do what you tell me. And so on. Hopefully.