In a recent post, Paul Krugman makes the following argument as to why the free market cannot provide health care:
You could rely on a health maintenance organization to make the hard choices and do the cost management, and to some extent we do. But HMOs have been highly limited in their ability to achieve cost-effectiveness because people don’t trust them — they’re profit-making institutions, and your treatment is their cost.
Yes, as opposed to the government (whom everyone trusts), where your treatment is my cost.