I don't think that every country will adopt bitcoin easily because here many countries already banned the bitcoin and many big countries allows to use bitcoin legally , but still there are many countries are like they. Are thinking that whether they legalise the bitcoin or not or regulate then how .
And also few people are using bitcoin for illegal work that is making the bitcoin's popularity more but use it as a legal and better thing is hiding its real use .
So may be it can take 4-5 years to accept Bitcoin by every country in future , but this is sure that everyone will accept Because they have no another option to have bitcoin .