I'm personally affected by illegal immigrants,they are the ones who cut the grass in my apartment complex.
And for just some historical perspective,the idea that immigrants would change america is a very old one.
The idea that the immigrants are unwilling to assimilate and adopt our anglo culture fully is nothing new at all.That is what happened when we let all those Italian and Irish in a century ago and they refused to become good protestants like the rest of us and clung to listening to some foreigner (the pope) as to what they should think and believe in.My grandfather a native born american of protestant Irish roots always talked about how the "C"s were ruining the country.
We are way to late to save america for a white anglo saxon protestant culture,needed to not bring over all those slaves and let all those ethnic catholics in (which the mexicans are just another variety of btw) to ever have any chance of doing that.
But I must say that in general I think the idea that any of these wave of immigrants (Irish,Italian,mexicans etc) have not been overwhelmingly people who have come to find economic opportunity and a better life and work very hard when they get here does not stand up to scrutiny.I may not be thrilled with some of their culture (the catholic church) but besides that they are good people.