In fact, you must contact the previous sentence to explain the meaning of the sentence you asked, otherwise it will be taken out of context. Americans like American assets more than foreigners, that is, Americans don't want their assets to flow into the control of other countries. American wealth mentioned later actually refers to American goods. The transfer of American wealth to foreigners will reduce the demand for dollar assets. In fact, it means that the United States will reduce its demand for dollar assets by increasing exports, which means that the United States needs to reduce its current account deficit. However, the situation of American exports is not optimistic, and the universally effective means to stimulate export demand is currency depreciation.