That is true. The only reason it works is because they have a commodity that they can sell that everyone wants (for now), that is just dug from the earth and so

That is true. The only reason it works is because they have a commodity that they can sell that everyone wants (for now), that is just dug from the earth and sold on the market with little cost/effort. Such economies are rare (and work because the other economies aren't the same). Also, they have a small life span and can easily not work (Venezuela).