The dollar is a global currency. In the American financial crisis, the United States needs to save these financial institutions, so it needs to inject capital into the market, that is, it needs to increase the amount of dollars, which will cause the dollar to flood and depreciate. In this case, there will be losses in holding US dollars, while the foreign exchange reserves of other countries in the world are US dollars, euros and gold, of which US dollars are the main reserves, and these assets will depreciate accordingly;
What's more, the United States has long issued treasury bonds, which have also been bought by other countries. When the dollar depreciates, the national debt also falls, which is also a loss. Finally, the depreciation of the dollar has led to a sharp rise in the prices of international commodities denominated in dollars, such as oil and food, which has pushed up the prices all over the world and caused global inflation.