Here's the problem in a nut shell. The treasury has to auction off 99 billion dollars in debt next week. That amount of debt will take us 4 billion dollars beyond the legal debt ceiling. Who forces the government to adhere to it's own rules, laws, or debt ceilings?
Nobody, of course.
ZeroHedge showcasing the math. http://www.zerohedge.com/article/treasury-hopes-auction-99-billion-bonds-next-week-can-it