Nothing racist whatsoever about it. It applies to any immigrant/potential immigrant of any race. And I agree wholeheartedly with the sentiment--if you are in the United States, and not a tourist, then, by damn, you should speak the language of the country, which, for the US, happens to be AMERICAN ENGLISH.
The only group who seems to think differently are the "La Raza" guys--who by the very name they chose, are the REAL racists. All the other non-English-speaking immigrants have learned the native languge and are, by and large, succeeding.
Maybe we should expel or banish Southerners with a drawl to wherever they came from until they learn to speak proper English, too, eh?