Goldman Sachs CEO Lloyd Blankfein recently suggested that the retirement age be raised. But is that truly the answer to fixing the ballooning Social Security deficit? Maybe not. That's because raising the retirement age is one of the more regressive ways to cut benefits, contends columnist Jordan Weissmann. Doing so would disproportionately hurt lower wages earners who generally have shorter lifespans than millionaires like Blankfein.