For China to challenge the dollar’s dominance it would have to demonstrate it has a stable economy which it does not have.
Furthermore it has been a long time since wealth was measured solely in gold. America is rich in natural resources which also count as wealth.
Nobody is going to bank of China which is still a quasi-third world country. A lot of wealthy Chinese are trying to move their money out of the country and most are choosing America as their landing spot due to our financial stability. Yes; we have a lot of debt but so does everybody else...
For China to challenge the dollar’s dominance it would have to demonstrate it has a stable economy
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Or a currency backed by Gold, presumably redeemable in Gold ( unlikely).