If I could jump into the assimilation thread a bit late: I am not in principle opposed to a governmental role in encouraging assimilation. I think, however, that less intrusion by the government into the culture will be necessary the fewer immigrants (legal plus illegal) there are, and the more places they come from. Assimilation under those circumstances will occur more naturally. The flip side of that is that the more immigration you have, and the more it comes from one source, the more aggressive an assimilative policy will have to be–and the less likely it will be, given modern political realities, that you will be able to have an aggressive policy.