New York Times.

As Republican presidential hopefuls trot out their policy agendas — which always involve cutting taxes on the rich while slashing benefits for the poor and middle class — some real new thinking is happening on the other side of the aisle. Suddenly, it seems, many Democrats have decided to break with Beltway orthodoxy, which always calls for cuts in “entitlements.” Instead, they’re proposing that Social Security benefits actually be expanded.

This is a welcome development in two ways. First, the specific case for expanding Social Security is quite good. Second, and more fundamentally, Democrats finally seem to be standing up to antigovernment propaganda and recognizing the reality that there are some things the government does better than the private sector.

Like all advanced nations, America mainly relies on private markets and private initiatives to provide its citizens with the things they want and need, and hardly anyone in our political discourse would propose changing that. The days when it sounded like a good idea to have the government directly run large parts of the economy are long past.

Yet we also know that some things more or less must be done by government. Every economics textbooks talks about “public goods” like national defense and air traffic control that can’t be made available to anyone without being made available to everyone, and which profit-seeking firms, therefore, have no incentive to provide. But are public goods the only area where the government outperforms the private sector? By no means.

One classic example of government doing it better is health insurance. Yes, conservatives constantly agitate for more privatization — in particular, they want to convert Medicare into nothing more than vouchers for the purchase of private insurance — but all the evidence says this would move us in precisely the wrong direction. Medicare and Medicaid are substantially cheaper and more efficient than private insurance; they even involve less bureaucracy. Internationally, the American health system is unique in the extent to which it relies on the private sector, and it’s also unique in its incredible inefficiency and high costs.

And there’s another major example of government superiority: providing retirement security.

Maybe we wouldn’t need Social Security if ordinary people really were the perfectly rational, farsighted agents economists like to assume in their models (and right-wingers like to assume in their propaganda). In an idealized world, 25-year-old workers would base their decisions about how much to save on a realistic assessment of what they will need to live comfortably when they’re in their 70s. They’d also be smart and sophisticated in how they invested those savings, carefully seeking the best trade-offs between risk and return.

In the real world, however, many and arguably most working Americans are saving much too little for their retirement. They’re also investing these savings badly. For example, a recent White House report found that Americans are losing billions each year thanks to investment advisers trying to maximize their own fees rather than their clients’ welfare.

You might be tempted to say that if workers save too little and invest badly, it’s their own fault. But people have jobs and children, and they must cope with all the crises of life. It’s unfair to expect them to be expert investors, too. In any case, the economy is supposed to work for real people leading real lives; it shouldn’t be an obstacle course only a few can navigate.

And in the real world of retirement, Social Security is a shining example of a system that works. It’s simple and clean, with low operating costs and minimal bureaucracy. It provides older Americans who worked hard all their lives with a chance of living decently in retirement, without requiring that they show an inhuman ability to think decades ahead and be investment whizzes as well. The only problem is that the decline of private pensions, and their replacement with inadequate 401(k)-type plans, has left a gap that Social Security isn’t currently big enough to fill. So why not make it bigger?

Needless to say, suggestions along these lines are already provoking near-hysterical reactions, not just from the right, but from self-proclaimed centrists. As I wrote some years ago, calling for cuts to Social Security has long been seen inside the Beltway as a “badge of seriousness, a way of showing how statesmanlike and tough-minded you are.” And it’s only a decade since former President George W. Bush tried to privatize the program, with a lot of centrist support.

But true seriousness means looking at what works and what doesn’t. Privatized retirement schemes work very badly; Social Security works very well. And we should build on that success.