My very simple perspective is this: In round numbers the US government debt increased by about $1,000,000,000,000 ($1 Trillion) in the single year between October 1, 2013 and October 1, 2014. Government revenue plus borrowed money were spent on the military, social security, Medicare and so much more. But that money is gone and producing NO future revenue, unlike debt that purchases a business which generates income to service the debt.