It happens that Richard formulated :
Yeah but if the U.S. went to Centigrade there would be one less way.
And I would not remember that the melting point of copper is about
1100 degrees but not remember if that is C or F. Or that a oxy acet
flame is 6300 degrees either C or F.

It is just one more way the U.S. is shooting itself in the foot as far
as trade.

How so? Nobody really gives a crap if the screws used to hold their
iphone together are inch, metric, Whitworth, or Klingon as long as they
hold the iphone together.

And - since they thread into plastic, any of the above will work fine!

Or even Coarse lol

--
John G