This paper by Amy Finkelstein and Robin McKnight, "What Did Medicare Do (And Was It Worth It)?" has a fairly novel take on the value of health insurance. In the first ten years of Medicare, it seems, the program "had no discernible impact on mortality." That seems to jibe with Phillip Longman's view, among others, that health insurance has played only a small role in improving longevity rates in the past. Now that doesn't seem like the best way to think about public policy, since at some level we should care about individuals rather than aggregate statistics, but there you go. Plus, as Harvard's David Cutler has argued, Medicare has led to the adoption of new medical technologies which will probably, in the long run, have a very large effect on mortality rates.

But whatever. Even if there aren't any health gains from universal insurance, Medicare did substantially reduce out-of-pocket expenditures for many seniors, and "the welfare gains from such reductions in risk exposure alone may be sufficient to cover between half and three-quarters of the costs of the Medicare program." This social insurance function, Finkelstein and McKnight argue, make the program "worth it" regardless of its value in improving the health of seniors.