In times of famine, Vladimir Ilych Lenin took a robust line on speculation. "We can't expect to get anywhere," he told the Petrograd Soviet in 1918, "unless we resort to terrorism: speculators must be shot on the spot."

Rather strong, perhaps, but the past week brought faint echoes of the sentiment. India's finance minister proposed shutting the country's agricultural futures markets. In Belgium, where the Belgian bank KBC has launched a fund with returns linked to food commodity prices, the Socialist party called for such funds to be banned.