Since the US is not a socialist economy...yet anyway...the majority of our economic growth comes from the private sector. And as our economy has evolved from an agrarian one to an industrial one to a service one, a larger and larger percentage of our economic growth hails from the service sector.
This and the fact unions have priced themselves out of competition doesn't help manufacturing either.
Regardless, if you look at where the majority of us spend our money domestically the majority of it is spent on services. Oh, sure, we buy X-Box's and PS2's, but those are manufactured overseas. Thus it should be no surprise that a vast majority of our economic growth is due to services.
Of course, what is the main engine driving this spending on these luxurious services?
"Precarious" is a word that comes to mind.