Bestow great attention on the Spanish language, and endeavor to
acquire an accurate knowledge of it. Our future connections with Spain
and Spanish America will render that language a valuable acquisition.
The ancient history of a great part of America, too, is written in that
-- Tho. Jefferson
You can't erase the cultural precedents before the expansion. Manifest destiny does not erase what was there before it. Many people don't even know that when California became a state its constitution was written both in Spanish and English. The presence of Spanish in this country is as important as Cherokee, Apache, etc, because much of American culture ties into Spanish America. We can no sooner eradicate the language than the Germans could eradicate French from Alsace-Lorraine.
And this has nothing do with people not learning english so don't be that dipshit who thinks they're going to come back with a clever comment. It'll be predictable but my reply won't :)