Bitcoin cannot become international until people all over the world have the bare necessities of life like food, water, medicine, clothing. After that the luxury comes = computer, internet etc. Also internet is the backbone of bitcoin, without which it is very much dead. So speculating that bitcoin will be international currency is just wild because there are still several places where basic amenities of life need improvement before some cyber coin which floats in thin air becomes popular there.
Well, if that is your criteria with bitcoin I think we can never consider bitcoin as an international currency, but for me I have a simple criteria and I believe bitcoin is a international currency as it is used all over the world and although not all people are using which I doubt will happen.