During debate over the health-care debate, liberal blogger Ezra Klein wrote that blocking the legislation would "cause the deaths of hundreds of thousands of people." The liberals were relying on a study from the Urban Institute saying 20,000 people die a year because they are uninsured. Free-market blogger Megan McArdle read the study and concluded:

when you probe that claim, its accuracy is open to question. Even a rough approximation of how many people die because of lack of health insurance is hard to reach. Quite possibly, lack of health insurance has no more impact on your health than lack of flood insurance.

Klein came back with this:

I don't want to be too harsh, and I don't want to imply that anyone is sitting around twirling their mustache thinking up ways to hurt poor people. But opposition to health-care reform (which is different than opposition to the people who would be helped by health-care reform) is leading to some very strange arguments about the worth of health-care insurance -- arguments that don't fit with previous opinions, revealed preferences, or even the evidence the skeptics are citing.

But today, with the fight over ObamaCare behind us, and the President dealing with expectations over what his bill can deliver, Klein has a blog post that goes much farther than McArdle ever did. Klein's headline:

Health care doesn't keep people healthy -- even in Canada

The main thrust of Klein's blog post:

The problem, the researchers say, is that the medical system just isn't that good at keeping people from dying. "Health care services use by itself had little explanatory effect on the income-mortality association (4.3 percent) and no explanatory effect on the education-mortality association," they conclude.

I don't want to be too harsh, and I've got nothing against what Klein used to call "arguments that don't fit with previous opinions," so I'll just recommend you spend more time reading Megan McArdle.

UPDATE: I should add that Klein, in his blog post, questions the importance of the Canadian data:

You don't want to over-interpret this data. It's possible that in the absence of insurance, the gap would be much wider. Indeed, there's good evidence suggesting that's true. Nevertheless, this should make us very skeptical about a world in which we're spending almost one out of every five dollars on health-care services. Universal insurance is crucial both for certain forms of health care and for economic security. But as I've argued before, it's probably not the best way to make people healthier. Rather, the best way to make people healthier would be to get health-care costs under control so there's more money in the budget for things like early-childhood education and efforts to strip lead out of walls, both of which seem to have very large impacts on health even though we don't think of them as health-care expenditures.