The future of English in America?

I have thought long and hard over the years about what I believe will be the national American language by 2050. If I'm deeply cynical, I'd say Spanish.
But, if I want to be level-headed, it'll be a form of English that will have changed deeply from what we currently know, with a lot more Spanish influence. What happened to English when the Normans mass emigrated to England, settled and became the ruling class will happen to American English, only with Spanish tweaking the tongue instead of French. This might actually cause the much-predicted rift between American English and British or Commonwealth English spoken by the rest of the world.
The most popular language, in a time when Hispanic family names like Gomez, Gonzalez or Hernandez will have completely overtaken Anglo, Irish, Italian or other surnames in phonebooks everywhere, will be the interaction between Spanish and English known as Spanglish. That will be a major, unavoidable dialect that will form the basis of much talk—and slang—among the majority of under 50s in the United States thirty-five years from now (if not sooner).
I believe most first-generation Latinos, even the offspring of illegal aliens, will learn English. But the case in which most offspring of Spanish-speaking migrants once were encouraged to learn and accept English only, the current—and certainly future—generations will have fluency in Spanish in their lexical arsenals as well.
Spanish-language media, such as Univision and Telemundo, aren't going anywhere and the market for Spanish-language news and entertainment grows stronger every year.
Now, don't misunderstand me: I don't appreciate this shift in culture and if I had my way, English would be forced upon Hispanics, the same way past immigrants had to be immersed in English and learn the language because there was no other option open to them.  And I also don't wish any American citizen to be told that they must learn Spanish as a foreign language.  I don't want the response to any American student who would like to study French, German, Russian or Chinese be: "No, that's stupid. Spanish is the language you should be learning."
However, to be practical, no other immigrant group in American history was poised to completely overrun the country the way that Mexican, Central American, South American and Caribbean speakers of Spanish are.
There will always be an incentive to learn English in America. At least that's what I want to believe. There will even be a sizeable portion of the Hispanic community that will defend English, just as there is today. But, to acknowledge reality, I think time will eventually come when the issue will be forced on us to go bilingual. Certainly the job market may dictate that.
Here's how I suggest we settle this matter once and for all:
The United States should establish Spanish as an auxiliary language. By doing that, we will not be declaring it equal to English. Español (or castiliano, if you will) will not be set up to be the majority or native tongue of Americans. It will simply exist as a recognized language of a particular community that speaks it, as it is in The Philippines. In order to bestow auxiliary status on Spanish, though, the country at some point soon will have to give English official status; English needs to be formally established as the primary language of the American nation.
This is an issue that has been forced on us by the sheer ineptitude of past administrations to admit to a burgeoning immigration and culture problem and effectively deal with it. There is no turning back, I fear. Let's just give Spanish its due with the auxiliary status fig-leaf and thusly prevent Canadian- or Belgian-style bilingualism that will polarize the country.
I assure you, the Nightdragon will continue to write in English, no matter what.