Just curious where you come up with this... I guess I've known far too many people not born in the US who actually do make an effort to learn English. My dad's first language wasn't English but he learned just fine. I'm pretty sure Luis' wasn't English either and same with his parents - they all learned. Same with quite a few friends who are Filipino. I could go on and on....
Yes you have some uneducated people not learning, but all people I know who have moved here have made an effort. Even my son's classmate's grandmother did her best to learn English and she only lives here maybe a few months out of the year before she heads back to her home country.
Having an official language isn't a bad idea. However if people think having an official language will help force the issue, I think that is short sighted. People will learn if they want to - not because it's "mandated"
I do think that when you live somewhere you should attempt to learn the language. I've only had one friend move countries like that (non-military that is) and she took the time to learn. She also taught her daughter to speak both English and native language.
Yeah yeah wall of text, suck it!
People tend to think that others are not making an effort without realizing that learning a second language as an adult is incredibly difficult for the vast majority of the population. Even learning a language as a teenager is significantly more difficult than learning it as a child. An adult without dynamic immersion classes will be struggling through the vocabulary and horrifying syntax of one of the most convoluted languages ever devised. English is a complete mess as a language and not very efficient, it's not surprise that people have a hard time. A 40 year old that's been here for ten years and is still struggling to speak english is also likely to be unintelligible due to his accent, something very difficult to lose.
Basically the argument only ever comes from people who have never spent a significant amount of time in another country and tried to learn a language as an adult. I've been trying to learn pashto since I got here and it's not easy despite communicating with afghans every single day. It would be a very long time before I would feel comfortable living here without a community of people that also spoke english.