For those that forget, the US did try to slowly go into the metric system in the 70s but only those of us that were 20 something or younger could figure out how to move that little dot back and forth. MOst schools didn't teach it until the early 60s.
Today we still have A lot of left overs from that little error in history. Try to buy A quart of soda. I can still remember working on my bikes and needing three different types of wrenches depending on where the bike was built.
That was no big deal, it was when I was working on something like A Dodge and needing two different wrench sets close to hand.
I can go either way, the metric system just makes too much sense but it gave my folks fits!!