For the first time, I bought an economics book looking for a point that bothered me: "Predatory State" by James Galbraith. The passage which he confirms my doubt is this. " And as the new global monetary system developed, the growing need for dollars-for monetary reserves-held outside the United States would come to guarantee that the United States would necessarily experience both trade deficits and budget deficits almost all the time." Many of other economists I try to follow via Mark Thoma's 'Economist's View" do not seem to emphasize this. This bit of understanding of just one sentence came from a discussion in Naked Capitalism. It may be long time before I understand any economics. The discussion is in the thread of Naked Capitalism. There is also a link to this summary of the book by Aaron Swartz.