S&P Downgraded US Bonds because government spending is on an unsustaianable path, and because the US took until the last-minute to increase the debt ceiling. In the recent debt-ceiling debate Republicans, driven by the Tea Party, insisted on putting government spending on a SUSTAINABLE path in exchange for additional borrowing. Democrats wanted the additional borrowing, but insisted on maintaining the current UNSUSTAINABLE path.
Now, it's true that both sides insisted on what they wanted, but these competing positions are NOT morally equivalent. Yet, that is exactly what the media narrative has been, as if the two sides were bickering over what color carpeting to put in the Capitol Hill office complex.
The fact is that one side is arguing for continuing the spending binge and the other side is arguing for living within our means. This is not a side issue, it is an essential debate over what kind of nation the United States will be today and in the future. Therefore, it is not an "adult" perspective to be exasperated with the inability to reach a "deal." In fact, impatience with seeing the debate through is a consummately childish behavior.