When it was instituted over 70 years ago, the statutory debt limit was intended to control congressional spending by limiting the amount of debt that the federal government could accumulate.
It has not fulfilled its legislative purpose. In the last ten years, Congresshas increased the debt limit ten times, raising the limit twice annually in 2008 and 2009. This data provides evidence that the debt limit, far from providing its intended fiscal discipline, has recently served as a symbolic cap that Congress will simply push higher and higher as spending increases dictate.
Any addict will tell you that they can't be cured so long as the fix is readily available and easily managed. Race for Justice has an interesting take on the situation in Illinois where debt is treated cordially, like an old, dear friend.