Why California is allowed to use Europe’s protected wine labels

Champagne, Chablis, Sherry, Chianti… these are all European wine labels which can only be used if a wine is produced in a certain region, and with a certain method. Champagne can only be produced in the Champagne region, using the méthode champenoise. Sherry is only Sherry if it comes from the Sherry Triangle in southern…