I've got a new Bloggingheads up with Raj Patel, the author of Stuffed and Starved, a book on world food policy. All of my Bloggingheads are, of course, must-see TV, but there's something a little extra special about watching the libertarian vegan debate the left-wing anti-globalization economist on trade, obesity, and public health.

One thing that I sort of whiffed was in explaining the debate over the role of developed nation farm policy in world poverty. There has been an argument for a while that farm subsidies are actually good for poor countries, because it provides them cheap food. The problem with this argument is that within poor countries, the farmers are almost always the poorest of the poor; almost all of the people living below $1 a day are subsistence farmers.

Suddenly we're seeing a reversal of the problem: rising world food prices are probably helping rural farmers (though it's not totally clear how much those farmers participate in the cash economy); urban workers, who are now getting hurt, are suffering and in some cases, rioting. There rarely seem to be unalloyed positive developments in the poorest countries.