On May 16, the United States Treasury auctioned off $72 billion in bonds, and as it did so, it reached the limit of its $14.294 trillion limit on how much it can legally borrow. But the world didn't end. Or at least the bond market -- the collective pool of investors that buy us debt -- went about its businesses as if nothing happened. A full on freak out by the bond market would drive up the cost U.S. borrowing and, according to Federal Reserve Chair Ben Bernanke, "destabilize" the financial system and "have extremely dire consequences for the U.S. economy."