Taper Time?

Tomorrow is the much anticipated December Fed meeting where we will learn (probably Thursday our time) whether they will taper QE or not.  If they politically feel the need to, it will likely be token in size and arguably fully priced in to the market already.  The fundamental questions remain though – with China and others clear in their statements of not wanting to buy more US treasuries, who will buy them if the Fed themselves stop?  They have purchased over 70% of them over the last year!  How will they contain yields (that have already doubled over the last 18 months) and maintain low interest rates – the very low interest rates that are essential to any recovery and their ability to pay the interest on their own massive debt. i.e. how do they stop the Ponzi scheme unwinding?