I don't understand how much $16 trillion ($16T) of debt is.  So, to help myself, I break it down to terms I can understand.

• There are about 254,000,000 registered vehicles in this country (2009 data).  Big number this is.  But dividing the number into $16T would give a valuation of about $69,000 for each of them.  This is somewhat higher than the average cost of automobiles on the road.  Another way to put it is to say the U.S. national debt could replace the entire U.S. fleet of automobiles with, for example, brand-new, fully equipped Lexus ES460s.  Nice cars. 

• The total of state budgets in 2010 was about $666B.  Dividing into $16T gives about 24.  This means the $16T national debt could completely cover all state budgets for about 24 years.

• The total annual foreign aid budget of the U.S. is reckoned to be about $54B.  Dividing this into $16T gives about 296, meaning that the national debt of the U.S. could cover all foreign aid for almost three centuries.

• The population of the United States is currently estimated at 312,780,968.  Dividing this into $16T gives the current encumbrance to each citizen of about $51,000.

• In 2008, 64.3 billion gallons of gasoline were consumed in this country.  It is surely higher now.  At $3.50 per gallon, this implies a total cost to the U.S. consumer of about $225B.  Dividing into the $16T yields about 71, implying that the U.S. national debt could pay for all gasoline consumed in the USA for the next 71 years -- assuming, of course, that annual consumption remains constant.

• In the month of October 2012, the monthly cost of home food for a family of four (liberal plan from the USDA) was about $1,100, making the annual cost about $13,200.  Multiplying this by the possible numbers of families of four (total population divided by four), the total annual home food costs to all citizens are roughly $1T.  Dividing this into $16T implies, in round terms, that the U.S. national debt could pay all home food costs for the next 15-plus years.  If we all ate with the USDA thrifty plan, the $16T U.S. national debt could pay all home food costs in the United States for the next 29 years.

That was fun.  So $16T is a really huge amount.  I still don't understand it much beyond that. 

There is a foundational lesson in all this.  The number 16T in dollars or any other measure is fundamentally beyond the comprehension of most of us.  And I work with big numbers all the time.  What is not taught in the schools these days, what is not anywhere the formal curriculum, and what is fully unknown to almost everyone is just what these big numbers mean, and how huge they really are.  Sure, it is easy to say that the speed of light (180K mps) translates into 180(mps) x 60(s/m) x (60[m/h] x 24[h/d] x 365[h/y] = 5,865,696,000,000 miles per year (~6 trillion miles).  But who really knows what this means -- in a visceral sense? 

Getting back to the $16T above, we caution two principal groups: Republicans and Democrats.  Neither side really understands anything about the true magnitude of $16T.

1. The Republicans: The public does not understand how much money this is.  Do you?  Don't compare with the GDP.  This is making a comparison of a quantity people don't understand with a quantity people don't understand.  It you wish to make a point, explain to folks how much money this is.  Do it in terms they understand.  My goodness, don't explain in analogy to Greece.  Most people don't know where Greece is, much less care about the Greeks' circumstances.

2. The Democrats: Be cautious about borrowing more money.  Understand the magnitude of what is already encumbered.  Think about this amount in terms you understand.  Understand the profound and massive effort required for the pay-back.

3. To both parties: Even if the economy came roaring back with whatever policy for job growth is promoted and enacted, the $16T debt is virtually beyond the capacity for repayment.  This country seems to be faced with default, or ultra-severe tax penalties on the next couple of generations.  For those aged over 50, the consequence is not that great.  The younger groups will be hit especially hard.