I can't reply to your comment, so I'll reply here (I'm not crazily replying to myself ... ) People need to obtain dollars from somewhere. If the total tax liab

I can't reply to your comment, so I'll reply here (I'm not crazily replying to myself ... ) People need to obtain dollars from somewhere. If the total tax liability in NewZims exceeds the number of dollars obtainable then people will have no choice but to use it. Also of note is that strong banking institutions are invaluable in this process. If people owe money in NewZims because of money created through private sector lending they'll also need to obtain them from somewhere in order to pay those debts. Making it illegal for banking institutions to hold accounts in currencies other than the national currency is also a means of avoiding this problem (ie. if people want to use banks they need to hold NewZims). Of course this all hinges on the ability of the sovereign to actually impose sufficient liabilities on the populous in the first place and it would take time for the new currency completely replace the foreign ones but it's doable and is the only road to long term repair of a nation unless they're accepting what amounts to being colonised again. You can't have sovereign government without sovereign currency.