[BorisVM]

Why didn't the United States ever switch to the metric system?

The metric system!? Where do you think you are -- some country that values logic? This is America, buddy. Home of hopelessly complex tax laws! Birthplace of the nonsensical Electoral College! For well over 200 years, thanks to tradition and good old-fashioned patriotic stubbornness, the U.S. Has been doing things that make no sense.

Well, that's not entirely true. The U.S. Has used the metric system since 1866, when Congress first made it legal. While traditional units of measurement like gallons and inches remain the default for everyday use, the country's scientific and business communities are longtime supporters of all things metric.

Readers might remember the government's attempts to bring the metric system to the masses. In 1975, Congress passed the Metric Conversion Act. Highway signs that once measured distances only in miles now listed distances in kilometers also. The Federal Highway Administration received thousands of complaints, so the project was soon abandoned. It seems you just can't teach an old motorist new tricks.

These days, the U.S. Is best described as a "soft metric" country, meaning it supports the metric system, but not exclusively. For example, buy a can of Coke and you'll notice it says "12 fluid ounces (355 mL)." Will America ever become a "hard metric" nation? Not bloody likely. Or to put it another way, when pigs fly at 100 mph (161 km/h).