If they assimilate, it won’t be a problem. So far, there is evidence that they likely will.
I have to disagree. There may be evidence that they'll eventually assimilate, but there's also ample evidence that they aren't and that they won't.
We didn't print government forms, including ballots in Italian, French, Polish, Hungarian etc, during the last great immigration boom. If you can't read English when you vote, no problem, someone will give you a Spanish-language ballot and directions. That's a future recipe for disaster.
Plus, none of those immigrants had a plethora of native-language entertainment options. Currently, there are two massive Spanish language national networks, that have beaten NBC in weekly ratings this last year. That's in addition to smaller, regional Spanish-language networks in CA and FL as well as every English-Language network simulcasting Spanish language audio for all their programs.
We seriously risk the Balkinization of several parts of this country. The Hispanics may end up assimilating, but I'd hardly call it likely at this point.