Economeeeooo!

   Let's pretend we're on an island. There are 20 of us. We only have access to what is on our island, so there are no import worries. We don't have a money system because everyone is just finding a place to live and helping each other when needed. I love carrots but can't grow them for squat. You hate carrots but are a world class carrot farmer, so I offer to trade you some of my crops for your carrots. 

   After awhile, we figure out that we have enough of each other's produce, so we start offering other things in return for what we need. I offer you a day's labor in exchange for help building a bridge between my bedroom treehouse and my bathroom treehouse. This bridge is especially necessary in the mornings. We can continue on like this forever without ever knowing we were supposed to be storing up stuff we don't need. 

   One day you come to me and say, "Can you help me build a radio out of a coconut? I'll give you some veggies!" I don't want any more veggies, so you offer to help me with any work I need, but I don't need any work done. So, you say, "How about if I give you this shiny rock as a promise that the next time you need work done or need veggies, I'll give them to you?" Tada! We have money! 

   This works fine, but we get tired of actually carrying around these heavy rocks, so we write on a palm leaf, "I promise one shiny rock in exchange for this palm leaf." When you finally come and add plumbing to my bathroom treehouse, which makes the people walking below extremely grateful, I give you a leaf and remember to set aside one shiny rock because it now belongs to you. 

   This system works really well for a long time, but someone figures out that if you never actually come to collect the shiny rocks, they can write leaves all day and get all kinds of goods and services without anyone finding out what they are doing. That is, not until one day they decide to come collect on all their leaves and you are fresh out of shiny rocks. 

   That's where America is now.