I believe that as a citizen of the US, you should speak English.  One should only be able to vote in English, or get a driver's license in English.  My grandparents came to this country, and needed to learn English to assimilate.  They maintained their cultural heritage, and continued to speak their native language, while learning to speak, read and write English.

We need to have one language.  People should be allowed to continue to speak the language of their native land, and if the demand exists, there should be TV stations and newspapers for them.  But the government should have a national language, and that language should be English.