The worry I've heard expressed is that China will come to a point where it won't be willing to lend to America at 2% interest. They will want more for their investments. Also, the interest on these loans will have to be paid. Other than the Pentagon every other area of Government is expanding. Obama will have to raise taxes to pay the interest on these loans and maintain his expanded government. Probably that will mean oppressive energy taxes. What better excuse to increase taxes than to say you are doing it to save the planet?
