The Federal Reserve keeps buying bonds to keep interest rates from rising. We have no choice but to default if creditors want their money back. If interest rates go up, we can’t afford that. That is why the Fed feels that it has to keep interest rates down at all costs. So the Federal Reserve prints more money to buy up bonds. That puts pressure on the dollar. Foreign central banks than buy those dollars to prevent their currencies form rising, which imposes costs on their own population, as they are forced to absorb our inflation.