They are being printed _how_?They are being printed...but I don't see what that has to do with my post.
What is the exact process how a new $1m of dollars (as a number in a bank account, not a pile of paper rectangles) springs into existence?
The answer is: it is usually born as US govt debt to FRS. FRS gives US govt a new, never before existing $1m. US govt gives FRS a Treasury IOU.
Since world economy is growing, US govt _has to_ go into more and more debt, in order to create more and more dollars for world economy.