One, a Ponzi scheme collects money from new investors and uses it to pay previous investors—minus a fee. But Social Security collects money from new investors, uses some of it to pay previous investors, and spends the surplus on programs for politically favored groups—minus the cost of supporting a massive bureaucracy. Over the years, trillions of dollars have been spent on these groups and bureaucrats.

Two, participation in Ponzi schemes is voluntary. Not so with Social Security. The government automatically withholds payroll taxes and “invests” them for you.

Three: When a Ponzi scheme can’t con new investors in sufficient numbers to pay the previous investors, it collapses. But when Social Security runs low on investors—also called poor working stiffs—it raises taxes.