If the three biggest buyers of US Treasury debt, the Federal Reserve, the Japanese, and the Chinese, are all selling Treasury debt, then who is buying Treasury debt? For now, it appears to be the Reverse Repo market. However, with only $1 trillion left in the Reverse Repo Market, the interest on the federal debt nearing $1 trillion annually, and $8 trillion of the $33 trillion of federal debt maturing next year, how long until the Fed has to turn around and act as the lender of last resort?