Yet, some countries have started willingly renouncing that monopoly.
For example, Australian Reserve Bank has clearly stated that "There would be nothing to stop people in this country deciding to transact in some other currency in a shop if they wanted to. There’s no law against that, so we do have competing currencies."[1]
Similarly, The South African Reserve Bank has come to the conclusion that "The Bank does not oversee, supervise or regulate the Virtual Currency (VC) landscape."[2]
[1] https://en.wikipedia.org/wiki/Legality_of_bitcoin_by_country...
[2] https://en.wikipedia.org/wiki/Legality_of_bitcoin_by_country...
1) These are bit players in the world economy, with nothing like the clout that the US derives from manipulating the world economy via seigniorage, reserve currency status, monetary policy and the ability to lock other countries out of the global economy
2) They will all change their tune if/when crytocurrencies start impeding the state's ability to make policy and collect taxes.
There's a digital currency in our future, but I guarantee that it won't be decentralized and that the government will have the signing keys.
That might be possible, but its too early to say anything at this point in time. The thing is that Bitcoin has technologically established itself as a stable crypto-currency and also an open-source wallet software. In future, some governments may also come up with their own centralized digital currency, but it will be too little and too late compared to something like bitcoin or litecoin.
Besides, bitcoin is international and a lot of people have started transacting in it already. Now, the government has to tread carefully about this, despite all the talk of sovereign nation and government upholding its economic control, no government can go against its own people in this day and age.
Also, actually persecuting the public for using crypto-currencies is against their own interest as it will create something like a Streisand effect. Right now, only the technically inclined know about bitcoins, blockchains and wallets, the rest treat it like some magical buzzwords. But if they start persecuting, a lot of other non-technical folks will also come to know about it and they will also start using it.
In short, the future depends on the mood of the people of the nation and not the governments. Its a fallacy that money begets is value as a legal tender by the government. Rather, it gets is value because its "generally acceptable", in other words the people accept it. People of a nation are above the government, not the other way round.
I feel like some Syrians would disagree.
You realize you can transact in any medium you want, right? Literally anything you want, as long as the other party accepts it. But this has nothing to do with the fact that you owe taxes on income, to be paid in dollars, regardless of the medium you choose.
I agree that the politicians in Washington will fight back to continue their monopoly. How people transact in private life has however no implication on nation state. USA as a nation state and we as people would be significantly better if Fed stops the business of regulating currency and simply replaces old note with new ones.
The fight on BTC is something that US government is bound to lose because the rate of innovation here has already surpassed the rate at which the pen pushers in Washington can pass a bill.