There was a time, not so long ago, when anyone with a proper education spoke French. Diplomacy and business were conducted in French. Knowledge was spread in French. Travelers made their way in French and, of course, lovers traded sweet nothings in French.
Viewed from France, the trouble with modern times is that many of those activities are now conducted in English, even by the French. In a country that cares so much about its language it maintains a whole ministry to promote it, that alone is enough to stir passionate debate in Paris.
But there is more.