Credit rating, Schmredit rating

WHAT?  OUR NATION'S CREDIT RATING AT RISK?

Moody’s Investors Service fired off a warning on Wednesday that the triple A sovereign credit rating of the US would come under pressure unless economic growth was more robust than expected or tougher actions were taken to tackle the country’s budget deficit.

In a move that follows intensifying concern among investors over the US deficit, Moody’s said the country faced a trajectory of debt growth that was “clearly continuously upward”. More here:

What?  Who cares about the credit rating of the US.  What's the big deal?  Those Henny Pennies should just  shut their beaks ... I mean, just relax ... what can happen? Right?  Right?  Bawwk, bawwk, cluck.

Do you mean to tell me that we can't just spend as much as we want without repercussion?  Why not?  This is quite the mystery!!