S&P? the one which repeatedly offered triple-A ratings to those junk securities before the GFC? It was sued by both US federal and state governments, eventually had to pay $1.5 billion fine for its wrongdoings.
Maybe S&P should fix its own credibility debt first?
How do you think they should do that, and why are you responding so defensively? It seems to me that the only way for them to build up credibility is to never repeat the mistake they made last decade - but you seem to think that they should respond to their mistake by ... never downgrading a credit rating despite seeing issues? That doesn't make sense.
You're wrong. Look at the comments below - you're reacting emotionally and not doing your research properly. I apologize if I'm mistaken, but I'm guessing you're Chinese. I've seen a lot of Chinese people get defensive over little things like this and respond with knee-jerk attacks, but it's really unnecessary. As your country gains influence worldwide you'll only see more articles like this - best get used to it and try to respond in a more useful way.
From where did you get $20 trillion? The data I see show $3.5 trillion for the United States versus $5.4 trillion for China [1]. U.S. depository institutions hold over $9 trillion in savings [2]; this doesn't count savings held in stocks and bonds, the majority of Americans' savings.
In any case, private savings aren't really relevant to a country's credit rating. Ability and willingness to pay are. If the U.S. Treasury defaults, one can sue. If China defaults...you're just screwed.
The Sydney Morning Herald article you cite [1] measures “deposits”. The comparable figure in the United States is $12 trillion [2]. The comparison is misleading, however, since few U.S. institutions, financial or non-financial, “save” in deposit accounts. (This is true in a China, too.) All this comes down to the murky definition of “savings,” which are in the end largely irrelevant to national credit concerns since “credit” is trying to quality their probability of seizure (through default, expropriation or other means).
You're right: judged only by those facts you give, this would seem to be absolutely insane.
And that's why you must be wrong. S&P may have made their fair share of questionable decisions, but they just aren't completely stupid.
I'm not saying that these ratings are gospel, now. Or that S&P isn't succumbing to, for example, political pressure in their ratings of the US. But presenting your case in such a way only damages your credibility, not theirs.
Maybe S&P should fix its own credibility debt first?
https://www.bloomberg.com/news/articles/2015-02-03/s-p-ends-...
China has over $20 trillion saved, S&P calls it a debt problem and downgraded their credit rating.
US has about $20 trillion debt, S&P is totally happy about it and gives it a triple-A rating.
https://www.bloomberg.com/news/articles/2015-06-25/with-21-t...
https://www.treasurydirect.gov/NP/debt/current
S&P is still the same old S&P, it didn't change in the last decade.