Don’t forget the influence of the petrodollar. Everyone uses the dollar not necessarily because they want to, but because the US has taken actions to ensure that oil can only be traded in dollars. This is part of why BRICS is seen as such a threat to US hegemony. If Saudi Arabia, Russia, and China are all agreeing to trade oil in something other than dollars, then suddenly the solvency of all of the economies of the world are far less reliant on the solvency of the dollar itself.