Over the past few months, we have seen several countries enter the Bitcoin era in their own way. While we are not yet at a point where countries buy Bitcoin with their treasure reserves, we do see many nations allocating part of their energy reserves to Bitcoin mining.
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I don't think poor countries will become rich engaging with Bitcoin but it can put positive impact on their economy. Because if a large number of people are engaging in crypto, their financial conditions will be changed, it will put their per capita income that will increase their GDP also.