I don’t use the word “proved” lightly. Her arguments are airtight; I can’t envision a rational rebuttal. Megan McArdle tried an irrational one, and hilzoy smashed it again. (Essentially, McArdle’s argument works only if one assumes away the nagging possibility that an American lacks health insurance.)
I wish I had something clever to add. I don’t. Just read it.
Update: Slight correction (though it won’t seem slight to any analytic philosophers reading!): Hilzoy did not, of course, prove that the condition of the uninsured must be called rationing, full stop. We can call anything anything we want. But she proved that on any reasonable reading of the claim that the Obama health plan (which wouldn’t ban supplemental insurance) would result in health care rationing, the label “rationing” would also apply to those now uninsured. If your currently well-insured aunt would be in danger of rationing under health reform, those now uninsured already face the same danger. Or, if you deny that the uninsured face rationing, you have to clam up about your aunt. If this is confusing, all the more reason to read hilzoy on the subject instead of me.