. Skipping down to the bottom line, we judge that the government's money is a short sale.

Diminishing returns is the essential problem of the debt: Past a certain level of encumbrance, a marginal dollar of borrowing loses its punch. There's a moral dimension to the problem as well. There would be less debt if people were more angelic. Non-angels, the taxpayers underpay, the bureaucrats over-remit and everyone averts his gaze from the looming titanic cost of future medical entitlements. Topping it all is 21st-century monetary policy, which fosters the credit formation that leads to the debt dead end. The debt dead end may, in fact, be upon us now. A monetary dead end could follow.

As to sin, Americans surrender, in full and on time, 83% of what they owe, according to the IRS—or they did between the years 2001 and 2006, the latest period for which America's most popular federal agency has sifted data. In 2006, the IRS reckons, American filers, both individuals and corporations, paid $450 billion less than they owed. They underreported $376 billion, underpaid $46 billion and kept mum about ("nonfiled") $28 billion. Recoveries, through late payments or enforcement actions, reduced that gross deficiency to a net "tax gap" of $385 billion.