Taxpayers aren't on the hook for "loans" made by the Federal Reserve. And we're in a liquidity trap - until the economy recovers and nominal interest rates rise above the zero lower bound, the Fed can print all the cash it wants without causing inflation (because people are going to save, rather than spend or invest, that cash). Which is pretty much what happened. The U.S. monetary base tripled between 2008 and 2011 and yet prices have not risen accordingly.