Since 1981, the U.S. government has borrowed trillions upon trillions of dollars, which would be okay if the borrowed money was put to productive investments like infrastructure, Research and Development, education, anti-poverty programs, etc. Productive spending creates more taxpayers and more jobs as entirely new industries are created.
For example, see the history of the internet (
http://en.wikipedia.org/wiki/Internet) which started as a government sponsored project in response to Sputnik and the creation of Defense Advanced Research Projects Agency (DARPA) (
http://en.wikipedia.org/wiki/DARPA).
This investment in R&D created an entire business paradigm shift for the better. Entirely new industries, companies, and jobs were created out of this kind of investment.
However, we didn't spend the borrowed money on productive projects. We spent it on tax cuts for the wealthy, obscene military war spending, stupid drug wars, prisons, and other wasteful projects.
For example, what economic benefit do we share for the invasion and occupation of Iraq? Where's the economic benefit to us as a nation? We spent $1 to $4 trillion dollars on that war, and we have nothing whatsoever to show for it. Imagine spending that money on education, health care, anti-poverty, etc. If we did, we'd have a healthier, more productive, less expensive work force that could compete in the global economy.
Also understand this, tax cuts means borrowing money and spending it on the wealthy. No amount of cuts can ever offset a tax cut on the wealthy. Tax cuts create budget shortfalls which is filled with borrowed money. Again, tax cuts equal borrowing and spending on non-productive investments.
That's why we're in this mess today.