I know as a conservative, a neo-Luddite (so UP says), and a Southern girl, I'm supposed to be in favor of the quaintly old-fashioned, nostalgia, and traditional things in general, and for the most part I am. But it is increasingly irritating me to have to convert metric measurements to the imperial measuring system. Why doesn't the US just switch? When I was a little girl in the seventies, "they" said we were going to switch. I saw things about the coming change on TV. In later elementary school we were required to do a section on metric measurements and do rows of tedious conversions from imperial to metric, because we'd be going to metric soon. As far as I can tell, the only thing that ever got done about it was that they started to make soft drinks in 2-liter bottles. And apparently this exhausted "them", because those early '80s textbook questions were the last I ever heard about it.
Oh, we were expected to know a little along those lines for some high school science classes and Coca-cola eventually released a 1-liter bottle. And of course people of various professions have to get comfortable with some metric measurements, which some of them no doubt had to do even before the government said we were going to switch. But the average American has no intuitive understanding of what most metric measurements stand for, the way we intuitively understand about what amount a cup of flour, a gallon of milk, or a footlong sandwich is. You have to have frequent contact with a measuring system to get that intuitive idea of how much a particular unit is. If you don't have those daily life type connections, the measuring system will always seem foreign to you.
Why don't we switch? Our not switching creates problems even in simple online situations, with US people not understanding non-US people's recipes--and sewing, craft, or DIY instructions--and vice versa. This is aside from any international business or government & military interaction problems that might be caused and which are probably more important than my petty dithering over dowel sizes and fabric bolts but which, OTOH, most of us, don't have to deal with as often as we might a foreign recipe.
It's not as if the American people are too stupid to switch. We've gotten used to the only metrically-measured thing most of us commonly see, the 2-liter bottle. We have no problem talking about mega this and giga that and health nuts or people with medical conditions necessitating reading food labels don't crumple when some of the nutritional information is given in grams. Our cultural heritage is predominantly British, and the British adapted to using the metric system just fine. (Although I have heard a few English grumblings about decimilizing their money when watching old TV shows.) Everybody else does it, why can't we? And it's not even as if it's a newfangled thing. Surely even conservatives can embrace something that's been around since the late 1700s.
I realize I could just start using it myself, but to be honest I'm lazy. I don't remember all of the formulas I "learned" as a kid, and I'm not going to go out of my way to use metric when everything around me is set up in standard US measurement. (Thanks to sewing, I have learned approx cm to inch and roughly how a meter relates to a yard, but I kind of had to and it's not so ingrained I couldn't forget.) And even if I did my own personal switchover and I wanted to, say, give a coworker a recipe, I would have to translate "my" measurements for other people. Better we should all be on the same page.