English is a so-called 'global' language. Many people learn English today because it is useful to know, and not because they like it or want to learn it.
Some learners are jealous of or angry at English, because it is a 'global' language, and their own language is a 'small' or 'minority' language. The popularity of English makes them feel as if their own language is somehow not good enough.
Still others feel that their own language, and culture, might be corrupted or perhaps destroyed by English, and they make laws against the use of it, or give their children the feeling that English is a 'necessary evil'.
English is very useful to know, that's clear. But is it a threat to other, strong national languages REALLY? And should you learn something you don't like, or don't want to learn, simply because it could be useful one day?