21 million coins is not enough to serve a country talkless of becoming world currency, I think we should start using Satoshi count more than the word Bitcoin. We also need fiat especially for the non-tech people
In line with your thoughts I also thought that the number of bitcoins in circulation could not handle the demand coming from hundreds of countries all over the world. If we are only talking of one country then that is very feasible but since we are talking about the whole world then that is another story. Aside from the insufficient number of coins in the circulation bitcoin cannot be controlled by the government placing the countries financially at risk.