Is Medicaid Something I Dreamed?

In his response to Whole Foods CEO John Mackey, Ezra Klein writes:

Food is more like health care than it is like cable television. We worry if people don't have enough food to eat. We worry quite a lot, in fact. So we have a variety of programs meant to ensure that people have sufficient food. If you don't have much money, you rely on these programs. As of September 2008, about 11 percent of the population was on food stamps. It's probably somewhat higher now. Millions more rely on the Women, Infants, and Children nutrition program, and reduced-price school lunches.

The insight that people need food has not led us to simply deregulate the agricultural sector (though that might be a good idea for other reasons) or change the tax treatment of food purchases or make it easier for rich people to donate to food banks, which is what Mackey recommends for health care. It's led us to solve, or try and solve, the problem directly by giving people money to buy food. And that works.

Last time I checked the United States has a means-tested health-care program called “Medicaid.” I take it that Ezra has not been arguing all this time for a program the country already has. Nor do I recall Ezra's arguments about health-care reform centering on the eligibility requirements for Medicaid. But why not? Wouldn't that work?