So I listen to people smarter than me. (Just like I don't attempt to be my own doctor).
This post at Daily Kos does a good job at explaining where we stand right now in detail:
But the summary version is this: We haven't seen any real economic gain over the past eight years despite appearances because the weakening dollar has masked the true state of affairs. Basically we have collectively done the following things simultaneously: Cut taxes. Started an expensive war. Deregulated the financial sector. Rode a credit/housing bubble.
Now the bill is coming due.