Missoulian: Three years into Gov. Brian Schweitzer’s first term, Montana has heard plenty about coal development. But a profound political shift is throwing serious coal plans here into limbo. The shift comes because of concerns over global warming, for "developing" coal means burning it – to produce electricity, natural gas or liquid fuel. And burning coal creates carbon dioxide (CO2), which is the prime suspect in global warming. Coal developers in Montana and across the nation expect …