So yes, I was mistaken. Carter wasn't a nuclear engineer. OTOH, the Carter Center website says "he took graduate work at Union College in reactor technology and nuclear physics." So bottom line is that he would have been very comfortable with the metric system, which was my point.
As for why we didn't switch to the metric system ...
First, this is a fun story about why we didn't switch in the 19th century:
In the experience in our lifetime, it was more about people objecting (and I know that Chuck Grassley seems to be a particular villain here). From
"America began testing road signs in kilometers under President Jimmy Carter, who supported efforts to go metric. Interstate 19, which connects Tucson, Arizona, to Mexico, was one of them and today remains the only highway in America with distances posted solely in kilometers.
"By the late 1970s, automakers had begun building speedometers that showed both miles and kilometers. Somehow, setting a cruising speed of 88 seemed so much cooler than 55.
"But the debate over whether to go metric was acrimonious.
"Metric supporters argued the road signs were a crucial step in helping Americans get over any psychological blocks to switching measurement systems. But Republican Charles Grassley, then a congressman and now a senator from Iowa, killed proposed federal regulations that would have forced states to put up signs in kilometers.
"'Forcing the American people to convert to the metric system goes against our democratic principles,' Grassley declared in June 1977.
"Grassley had plenty of supporters in America. Anti-metric Americans came out of all corners and formed an unlikely coalition to make sure this country did not give an inch. They ranged from author Tom Wolfe to NPR chief Frank Mankiewicz."
Doesn't seem like Carter's to blame.
Tamar