Every currency has a place where they belong. The only deal here is not about taking over a country's local currency, but about making it general accepted, which could be used globally in times of payment just as the United States dollar is being used in most major international markets.

To me, it's insane to even think about using Bitcoin to replace an entire country's local currency. No doubt, it can acquire global recognition in the coming years to the extent that people will want to use it in every part of their purchases, but that will not still qualify it to be a whole country's local currency. I think no digital currency can serve that purpose; it's a country we are talking about here, not just an extended family or a small town filled with selected numbers of people.

I said this because Bitcoin has all the features that make it qualified to be called money, but to me, some things are still missing for it to be used as a local currency, which are the limitations it has when it comes to conducting and concluding transactions without the use of the internet. A transaction can't be considered complete since it can't be broadcast into the blockchain.
How do you expect the old people who are too old to be using the computer system or even their personal phones to be making purchases? When it comes to a small amount of buying products that seem to be costing below a dollar, how will you expect to be making such a payment and spending more than 30% of your payment as a fee?