Offer your thoughts or opinion on the input financial query or topic using your financial background.

Why so much noise about USA's credit rating being lowered?
Because US bonds have had the prior impression of absolute invincibility and safety that has helped the dollar become the world's reserve currency and the United States borrow essentially at will. For the people that care what S&P says, the aura of invincibility is broken and it is conceivable, in SOME universe, for the US to default on its debt. This is of little practical importance on its own, but it's yet another signpost on the road to Chinese or European economic hegemony.