I'm not sure whether you're intending to pose that as a problem -- why should language be a barrier to anything? It could open the possibilities to a lot of people in less well off countries.
What would be a problem (and is kind of assumed in what you're saying) is if people stopped learning their native language in favour of English.
Yes, and I meant to say that would be a bad thing. For example, Welsh is compulsory in schools in Wales where most will know English fluently, there is quite a political effort to keep it going.
The OP originally struck me as a negative comment but reading it again makes me think it was more of just an observation.
I wasn't trying to say having one language is a good/bad thing, but everyone having say, a common language, could benefit all as it opens up more possibilities with people.
I'm not sure I came off right in the second sentence. I meant as if people only chose English and leaving behind their heritage / culture (as amichail suggested below) that would be bad.
Yes, I'm an English only speaker (I believe the majority of the world are bilingual now too), and so are my parents :)
Im living at persent in Oslo, young and old talk about how english has altered Norwegian. Words have krept in, some phrases are now said in english. I think a common language would accelerate the decline of many languages with small populations.
What would be a problem (and is kind of assumed in what you're saying) is if people stopped learning their native language in favour of English.