The characteristic of any Ponzi scheme is that the people being paid out are paid out with the money put in by later payers. By any realistic definition, social security is a Ponzi scheme. The money paid in by the people who got in early has not been saved or invested. It has been "borrowed" into the general fund with the issuance of IOUs called bonds and then the money is spent. The problem is that then the government encourages abortion which eliminates a lot of potential payers, and they decide to expand the program to do things it was never intended to do which means it costs more and slowly the number of people paying in relative to those being paid out has declined and is rapidly, like all Ponzi schemes, approaching unsustainability. EIGHT YEARS AGO it was unsustainable. What has changed? Nothing of substance.