A reader goes beyond the utility of the language:
In my opinion, one doesn’t learn French for practical reasons (although one of your readers did make a case along those lines). Rather, one learns French because it is beautiful. Some of the most adventurously intellectual, rigorously philosophical, and inventive, artistic, and creative minds just happen to have been shaped by the French language. To mention only a few examples: the poets Baudelaire, Verlaine, Rimbaud, Mallarmé, Apollinaire, Jacob, Valéry, Artaud, et. al. The list of French philosophers is even longer: Abelard, Montaigne, Descartes, Voltaire, Diderot, Comte, Bergson, Sartre, de Beauvoir, Barthes, Foucault, and the rest.
I could go on listing French composers, playwrights, novelists, scientists, and the like. But to my mind the best defense for the French language is an Irishman:
Samuel Beckett wrote some of his most important works in French, including his masterpiece Waiting for Godot and the trio of novels Molloy, Malone Dies, and The Unnamable. Beckett consciously chose to write in French, because it freed him creatively and allowed him to develop a style that he would not have developed otherwise.
Language both shapes culture and is a reflection of culture. To rate languages accordingly to how “useful” they are, as McWhorter does, is peculiarly vulgar and offensive. It also indicates an oblivious attitude toward the beauties and mysteries of all languages, not only French.
As a French major, I can say that studying la langue was great. But not for Molière or Rimbaud. (Yes, for Paris …) Rather, it’s the way one’s brain stretches and re-forms when confronted with alternate cultural architecture for seeing, sorting, and comprehending the world around you. To discover, for instance, that the French language has no word for “wilderness” – for a kid from the West, that was a mind-blower. “My cultural foundation does not exist in your worldview.” That is why language is such a powerful thing to study.
American children need more opportunities to be shocked out of their America-centric universe, and to see that meaning is fleeting and culture-dependent. If the temptation of croissants and a sweet tooth for Orangina gets a kid to study French, bravo. Whatever the language, the better a child (or adult) will be for it.