The conventional wisdom that nearly infinite demand exists for U.S. Treasury debt is flawed and especially dangerous at a time of record U.S. sovereign debt issuance.

The recently released Federal Reserve Flow of Funds report for all of 2011 reveals that Federal Reserve purchases of Treasury debt mask reduced demand for U.S. sovereign obligations. Last year the Fed purchased a stunning 61% of the total net Treasury issuance, up from negligible amounts prior to the 2008 financial...