In Portugal there are people from: ex-colonies in Africa(speak Portuguese), Brasilians and Timorenses (speak bad Portuguese), Eslaves (Russian or similar, much more common since 1989) and Gipsys (they seem to us as hispanians seem to US people). Portugal is small but there are plenty of differences between different regions (Minho, Oporto, Center, Interior, Lisbon, After Tagus, Algarve, Madeira and Azores).
However, Portuguese is essencial to live here. One of this days, I heard in the news that a former vice-minister of work of an ex-soviet republic is working as a stonemason here due to lack of Portuguese. And all the labor in major contructing companies is done by eslaves who have degrees in medicine, economy or something like that.
I see TV (US series...) so I think I know what you are speaking about. Chinatowns, Little Italies and Hispanian ghetos proliferate in US biggest cities. Inside them, people doesn't need to speak in English. Even Portugal has a street like that (in New Jersey, next to New York) where you don't need to speak other language than Portuguese and the 10th of June is celebrated.
Speaking english is not so important in US because a larger country can support larger comunities that can support easily non-english speaking persons.
However, you cannot escape from this: English is dominant!
The US president does all his speaches in US English (he only said some words in spanish during the campaign to capt votes from some of the 20.000.000 hispanians the US has...)
The main TVs transmit in English. Other TVs have little share from market niches.
The institutions like the supreme court and the army have names in English.
...
I know English is not the ONLY language in US. And even that some people live in America without even knowing English.
But to put in question that English is the official US language... I would like (Who vote for Portuguese?

), but I can not.