Mitt Romney and Rick Perry’s exchange about Social Security during the last debate at the Reagan Presidential Library drew a lot of attention for various good reasons. It showed that Romney was willing to criticize Perry “from the left” on an important federal domestic program. It showed that Perry isn’t backing down on a radical approach to entitlement programs, at least for people who aren’t over or near the retirement age, and that he won’t directly retract his attacks on Social Security and Medicare as immoral and un-American. And arguably, it showed that Perry, the new consensus Republican front-runner, is willing to run a pretty big risk in electability in order to protect his right flank and make Tea Party folk happy.

But if all these implications of the Romney-Perry clash are reasonably clear, there is a more subtle but possibly even more significant additional consequence of Republicans arguing over whether to demolish or merely slash Social Security and Medicare: It will materially aid Barack Obama’s high-stakes effort to make the 2012 presidential election a choice between two very different visions of American government, rather than a referendum on his administration and its handling of the economy.

FOR THE PRESIDENT, the whole ballgame is to convince voters that it’s not possible simply to fire him and bring in fresh new management, or even to repeal Obama “mistakes” like health care reform or the 2009 stimulus legislation. According to the preferred re-election narrative, a Republican victory will not mean going back to November of 2008—bad as circumstances were at that juncture—and starting over. It will mean inviting a radical experiment in domestic government that involves shredding a social safety net, a set of basic regulatory policies, and a modern federal government that were put together painstakingly by Republicans and Democrats from the late 1930s onward.

Republicans, of course, will resist this interpretation of the choice and will insist they are simply reining in a runaway federal government led by arrogant and incompetent vote-buyers who are wrecking the economy in order to consolidate still more power in Washington. That’s why the more radical intentions that the conservative base is urging candidates to pursue are so often couched in dog-whistle code language like “constitutional conservatism,” “restoring the 10th amendment,” and liberating “job creators.” And even Perry is now trying to refashion his criticism about Social Security into an argument about its current condition—the “monstrous lie” that this “Ponzi scheme” can keep its promise to younger Americans without a severe curtailment of benefits or abolition of the entitlement altogether.

It’s already too late, however, for Perry to backtrack on his fundamental objection to Social Security, Medicare, Medicaid, federal aid to education, and federal environmental protection laws. In Fed Up, Rick Perry usefully and repeatedly communicated this radical message without bothering to encrypt it, fulminating not just against Obama or Barney Frank or public-sector union bosses or other contemporary bugaboos, but against virtually every expansion of federal power since the earliest stages of the New Deal. And having essentially proposed a referendum on the policies of Franklin D. Roosevelt and Lyndon Johnson and Richard Nixon and Bill Clinton and both Bushes, he has decided to stick to his guns.