Offer your insights or judgment on the input financial query or topic using your financial expertise. Reply as normal question answering

Why so much noise about USA's credit rating being lowered?
Dollar is the lingua franca of the financial industry and unluckily it is the US currency. It is till today considered the most safest investment bet, that is why you have China possesing $3 trillion of US debt, as an investment albiet a very safe one. Financial investors get in queue to by US bonds the moment they are put up for sale. Because of the AAA rating the investors consider it to be safe at a specific rate. Now when you lower the credit rating you are indirectly asking the US government that you want a higher return(yield) on your investments. When you ask for higher yields, it translates into higher interest rates (money US would get for bonds issued decreases and so more bonds are issued). So you basically start looking at a slowdown in consumer spendings households and businesses. With already defaults, repossesions and lesser spending, the slowdown would increase manifold.