The “2012 or never” hypothesis helps explain why a series of Republican candidates, first in the House and most recently at the presidential candidate level, have taken the politically risky step of openly declaring themselves for Paul Ryan’s radical blueprint. Romney’s campaign has been floating word of late that it sees a potential presidency as following the mold of James K. Polk — fulfilling dramatic policy change, and leaving after a single term. “Multiple senior Romney advisers assured me that they had had conversations with the candidate in which he conveyed a depth of conviction about the need to try to enact something like Ryan’s controversial budget and entitlement reforms,” reports the Huffington Post’s Jonathan Ward. “Romney, they said, was willing to count the cost politically in order to achieve it.” David Leonhardt floats a similar sketch, plausibly outlining how Romney could transform the shape of American government by using a Senate procedure that circumvents the filibuster to quickly lock in large regressive tax cuts and repeal of health insurance subsidies to tens of millions of Americans.

Blowing up the welfare state and affecting the largest upward redistribution of wealth in American history is a politically tricky project (hence Romney's belief that he may need to forego a second term). Hence the Romney campaign's clear plan to suture off its slowly declining but still potent base. Romney’s political-policy theme is an unmistakable appeal to identity politics. On Medicare, Romney is putting himself forward as the candidate who willoutspend Obama, at least when it comes to benefits for people 55 years old and up. Romney will restore the $700 billion in Medicare budget cuts imposed by Obama to its rightful owners — people who are currently old.

He will cut subsidies to the non-elderly people who would get insurance through Obamacare — a program that, Romney’s ads remind older voters, is “NOT FOR YOU.” Romney’s repeated ads on welfare, blaring the brazen lie that Obama has repealed the welfare work requirement, hammer home the same theme. The purpose is to portray Obama as diverting resources from usto them.

In their heart of hearts, Romney and Ryan would probably prefer a more sweeping, across-the-board assault on the welfare state. But the immense popularity of the largest, middle-class social insurance programs like Medicare and Social Security force them into the divide-and-conquer gambit. They can promise to hold their disproportionately old, white base harmless and impose the entire brunt of their ambitious downsizing of government on young, poor, and disproportionately nonwhite Democratic constituencies.