I'm tellin' ya, pretty soon the onus will be on Americans to learn Spanish.
In LA, where I live, that is already the case. It is "insensitive" to ask an immigrant why they can't speak English, even if they've lived in the U.S. for 20 years or more. But I wish I had a dime for every time someone's said to me, "You've lived in LA HOW long, and you still don't speak Spanish?!"
Too late - already is in many areas. Here in Arkansas, if you want a job in many locations, particularly in the NW part of the state, you have to know Spanish if you hope to get hired for many jobs.
And forget getting a job as a school teacher in that same region if you don't speak Spanish ---it's a requirement now.
Our "free-market" system is going to force the language on us, regardless of the law. As is told in the quotes from TR, immigrants should "become American" - including the language (English). Yet that has been thrown out the door. we no longer expect immigrants to learn the language (at least Hispanic immigrants).