Christian Science Monitor: Record prices for grain from corn to rice have ignited food riots from Jakarta to Rome. In Pakistan, troops now guard wheat stocks. China and Russia have imposed price controls. Connect the dots and there’s a need for a fix to a crisis that, strangely, isn’t caused by smaller harvests. No, the main reasons for a long-term bubble in grain prices lie largely in a number of dubious human actions, related to heightened competition for grain as either fuel or feed. One reason is an …