The implication is really the other way around. The USD was the reserve currency in part because of the credibility of the US government's financials (and also

The implication is really the other way around. The USD was the reserve currency in part because of the credibility of the US government's financials (and also because of amount of trade, etc). But obviously, the US has taken a huge beating credibility-wise recently. After all, Sterling used to be the world's reserve currency : things change.