I think you're totally right when you talk about going to other countries and respecting thier cultures, but I can't say I agree to your view on the English Language. Everyone knows that English is the dominant language in the United States and in the economy.
Minorities know that.
In fact, I highly encourage the teaching of secondary languages as a part of the high school curriculum. I see this all too often in the computer classes I teach where those students who have difficulties with English always have more trouble than their peers. English in American schools should be fundamental and even more important than other basic curricula such as mathematics, science, history, and literature. While it's bad when a high school graduate has no idea what logarithms or light-years are, which side won the Civil War, or who wrote Hamlet, that person could still get along despite those holes in his knowledge.