No doubt, in 100 years Mexican-American snobs will be looking down their noses at [insert next immigrant wave] and making dire predictions about the decline of American culture.
I hope you are right, but I don't think so. My knowledge of history leads me to believe that 100 years from now this country will be a balkanized region of half a billion mostly poor souls, separated into dozens of third-world cultures, with a small number of rich elite running a massive, totalitarian welfare state that will make the Stalinist excesses of the former USSR look like a paradise.
In 100 years there will be no Mexico or United States.