In general, governments ought to liberalise markets, not intervene in them further. Food is riddled with state intervention at every turn, from subsidies to millers for cheap bread to bribes for farmers to leave land fallow. The upshot of such quotas, subsidies and controls is to dump all the imbalances that in another business might be smoothed out through small adjustments onto the one unregulated part of the food chain: the international market.
For decades, this produced low world prices and disincentives to poor farmers. Now, the opposite is happening. As a result of yet another government distortion—this time subsidies to biofuels in the rich world—prices have gone through the roof. Governments have further exaggerated the problem by imposing export quotas and trade restrictions, raising prices again. In the past, the main argument for liberalising farming was that it would raise food prices and boost returns to farmers. Now that prices have massively overshot, the argument stands for the opposite reason: liberalisation would reduce prices, while leaving farmers with a decent living.