> For most of the 20th century it had by far the greatest real productive and manufacturing base of any country in the world. The USA has been visibly declining

> For most of the 20th century it had by far the greatest real productive and manufacturing base of any country in the world. The USA has been visibly declining for about 45 years sure, and is no longer the world leader in manufacturing, but it still has a huge and well-diversified economy. Since dollars represent, among other things, claims on a share of that economic output, demand for them is quite real and not just an historical artifact. This is merely viewing the same thing from a US-centric perspective. From a rest of the world perspective, the largest competitors in EU were destroyed in WW2 (deservedly so imo), China was nowhere and India was impeded first by British colonization and then by Bretton Woods which only focused on EU nations. America is ahead but make no mistake that the gap is large only because WW2 destroyed other nations and Bretton Woods system was the first step in prevention of other nations from building up rapidly.