The advantages of having a second language are more than just having an ability to communicate with people from another country, although that is very beneficial of itself. There are many cognitive benefits of learning a new language:
Improves ability to concentrate
Learning a language through immersion i.e. living in a country where that language is spoken, has been shown to improve mental alertness and awareness.
Research has shown that those who learn a second language have more empathy with those from other cultures. This is particularly significant if you are learning a language in order to move to another country.
Multiple studies have shown that learning a second or third language also helps your memory. It has been shown to improve memory recall, names etc. however most significantly it can also stave off the effects of age-related dementia.