Wedding bells are in the air between Italy and France's flagship champions of state-backed industry. The Fiat-Chrysler-Renault merger would create the world's third-largest automaker. Perhaps even the first - but only if Renault's alliance partner Nissan signs on. Nissan was left in the dark over negotiations after resisting a full merger with Renault. It will have to decide if it is willing to trade market share for autonomy. Someone will probably have to swallow a whole lot of national pride.