Yes, I am of Mexican desent on my mother's side. They've mostly been here since before the Republic of Texas and stayed because this was their home. They all learned English and most of them are very successful. I do have a few cousins who are supporters of the Aztlan movement. It makes for interesting family get togethers. Most of my family is very anti-mojado.
On my father's side; his father's mother was one of the Hoosiers KSFreeman spoke about whose family had to learn English when they came over from Germany some time in the 1800's. There are still quite a few Nagels in the Salem area. Those that I've met all spoke English and consider themselves Americans first.
Not that I've had to ask. Most are veterns of WWII, Korea and Vietnam and would kick my butt if I made them think I doubted their patriotism (unlike the Aztlan crowd who'd kick my butt if I said that English should be our national language).
All said (and I've said it before), I respect my ancestry but consider myself a citizen of the USA first, last and always.