Just read Jonathan Chait’s TNR piece in favor of Democratic obstruction on Social Security. It’s well done, even if I disagree with it. But this is a revealing bit. Chait argues that Democrats have to stop accounts now because the public would like them and demand their expansion and liberalization:

Conservatives believe, not without reason, that private accounts will offer an invidious comparison to traditional Social Security. Workers will note that the taxes they send off to the traditional program disappear, while the money in their own accounts grows before their eyes. The private accounts will, in most cases, also appear to provide a higher rate of return. As noted above, the comparison is deceptive–traditional Social Security will be bearing the weight of the legacy debt, disability benefits, and, for affluent workers, redistribution to those earning less. But the comparison will create a constituency clamoring for expansion. Conservatives once proclaimed this unabashedly. The 1983 Cato Journal paper, which advocated what it called a “Leninist Strategy” for undermining Social Security, argued, “This mechanism for demonstrating the individual gains and losses that occur under Social Security is a key step in weakening public support for our present system.”
Today’s privatizers offer assurances that private accounts will be strictly limited and regulated. But those promises can’t easily be reconciled with one of their key selling points–namely that workers would own them. “Under a privatized Social Security system, workers would have full property rights in their retirement accounts,” writes Cato’s Tanner. “They would own the money in them, the same way people own their IRA’s or 401(k) plans.” The comparison with IRAs and 401(k) accounts is instructive. These, like the proposed Social Security accounts, were created for the very narrow purpose of retirement savings. But their owners saw them as their own property and demanded the right to use them for children’s educations, buying homes, and other purposes. Congress has steadily acceded to those demands, and the Bush administration has already proposed expanding IRAs into all-purpose tax shelters with even fewer restrictions.
As conservatives well understand, once a group of voters has been given a property right by Washington, they will never allow it to be taken away. The individual rights will be a ratchet, one that can be expanded but never contracted. The pressure for expansion would be especially strong during extended bull market runs, such as during the late ’90s, when the public (and even some economists) tends to delude itself into thinking that stocks will rise forever. This is why conservatives are so insistent upon establishing individual accounts. They have uncharacteristically volunteered compromises–even offering to violate their theological opposition to tax hikes–in order to insert their opening wedge. Privatizers understand full well that any concessions they make can be legislated away in the future, while private accounts cannot.

This is a tidbit I’ll have to put into my quiver for later use: “Even liberal Jonathan Chait says the public would LOVE personal Social Security accounts.”