I'm impressed by the fact that the response so far to my post on cost overruns in the Massachusetts health care program has so far been met by . . . changing the subject. "Well, what are you planning to do to cover the uninsured?!" or "Private health care costs have grown even faster than public costs!"

These are spectacularly irrelevant to the question of whether covering the uninsured will cost much, much more than estimates. Every major health care program we've put in place has cost much more than promised. This, presumably, matters. The first step to assessing the costs and benefits of something is, well, knowing the costs. Obviously, the budgetary cost is only one cost, but it is a component of the larger pricetag we should hang on any national health care program. It is therefore important to know what that actual cost will be. The answer appears to be "Vastly higher than whatever its advocates are promising."

When you respond to this point by saying "But look at all the benefits!" the message you are sending is "I like this program, and I don't care whether the numbers used to sell it are wildly inaccurate." That's not exactly a stunning rebuttal of my point.

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