What's wrong with calling SS a Ponzi Scheme? That's exactly what SS has become—the only source to make future payments is from future receipts, past payments were only partially invested, and the invested portion was “invested” in US IOUs, and then spent.
Why would such a comment, which is telling the truth, bother conservatives?
It's about timing. Calling SS a Ponzi scheme is one of the few truthful things Perry has ever said. But to say it while in the midst of a national election is political suicide. Obama and the DNC are sure to play it for all it is worth.
Perry needs the votes of seniors and Independents if he is to have any chance of getting elected. Given that many will buy into the DNC's condemnation of him with talk that he wants to cut their SS checks. Do you really not see how that has or can hurt Perry?