Legislators in Prague took a historic vote last week: by a landslide, they renamed their country the Czech and Slovak Federative Republic, removing a hyphen they had inserted only four weeks earlier. The new monumental mouthful was a concession to the country's 5 million Slovaks, who have resented the dominance of the 10 million Czechs ever since the country was formed in 1918 from the Austro-Hungarian empire's two western Slavonic provinces.
The March 23 decision to name the country the Czecho-Slovak Federative Republic was intended to appease angry Slovaks. Instead, it only increased nationalist ire. In the following weeks thousands marched...