900
The internet wouldn't allow this
(startrek.website)
People tweeting stuff. We allow tweets from anyone.
RULES:
We have to exist in a context that resists it. The weatherman will tell you the temperature in Fahrenheit. The road speed limit is listed in mph. You buy milk and gas in gallons.
If anything, Americans who force themselves to use metric in everyday use are working much harder at it than any European.