in his column in 9 news and world report mortimer zuckerman drew back on the clear and present dangers of the debt and future unfunded obligations. quote, over the last four years, our national debt has grown by more than $5 trillion to over $16 trillion. we have to service that debt. the federal reserve is keeping rates historically low, but here is the course of paying interest on the debt for fiscal 2012. -- the cost of paying interest on the debt for fiscal 2012. $359billion plus. what do you get for that? nothing. the greatest fiscal challenge to the u.s. government is not just its annual deficit, but its total liabilities. our federal balance sheet does not include our unfunded social insurance obligations. medicare, social security, and the future retirement benefits of federal employees. only in the small print of the financial statements do you get some idea of the enormous size of the unfunded commitment. today, the estimated unfunded total is more than $87 trillion. that's 550% of our current gdp, gross domestic product. and the debt per household is more than 10 times the m