Since the US Goverments options were run down to zero by succesive admininstrations digging a deep financial hole the taxpayers can never hope to climb out of, I personally believe this repeated money printing is a deliberate strategy to deflate the real value of the foreign debt.
There will be a great deal of pain suffered as the cost of imports (notably oil) rise, but the amounts to be repaid will lowered against real purchasing power. A “least worst” option if I ever saw one.