Other counties need dollars to settle their international trade (particularly oil but practically a lot more), and to hold in reserve. The dollar is actually th

Other counties need dollars to settle their international trade (particularly oil but practically a lot more), and to hold in reserve. The dollar is actually the only currency that's been printed enough to serve this purpose alongside its other benefits. This demand for dollars makes the US less attractive to import from as the price of the dollar is driven up by this extra demand.