Chrétien's French isn't that great either. (The joke among francophones is that he doesn't speak either of the official languages.) But he made himself understood by speaking with his heart, which was Dion's failing. Being from the academic world, Dion's motus operandi is to be cerebral in his speech, which doesn't come across well in politics even in your native tongue, let alone a second language he didn't master well. Dion's French on the other hand is impeccable, which made him an able proponent of federalism and a worthy opponent to Lucien Bouchard when he formed the government in Quebec. Dion, as Chrétien's Minister of Intergovernmental Affairs, was more responsible than anyone else for the decline of separatism in Quebec.