Growing up (as I did) in the province of Québec, you learn not just the joys but also the perils of bilingualism. A separate national identity, revolving entirely around "Francophonie," became a raging issue that led to social unrest, terrorism, threats of separation and a referendum that came within a hair's breadth of breaking up Canada.
Canada, of course, had no choice about bilingualism. It is a country created of two nations at its birth, and has ever since been trying to cope with that inherently divisive fact. The U.S., by contrast blessed with a single common language for two centuries, seems blithely...