Why are so many electric cars (still) only sold in California?

CARB ZEV vehicle game board 2018Car buyers don't have to live under California's golden sunshine to want electric cars. Yet, in some months, buyers in California purchase more than half of all the electric cars sold in the U.S. According to reader Mike Kamm (H/T Mike), even several of the electric cars that used to be sold in the Northeast are now nearly impossible to find on...