This essay was originally published on TomDispatch and is reprinted here with Tom's kind permission. ----- Gas prices are above $4 a gallon; global food prices surged 39 percent last year; and an environmental disaster looms as carbon emissions continue to spiral upward. The global economy appears on the verge of a TKO, a triple whammy from energy, agriculture, and climate-change trends. Right now you may be grumbling about the extra bucks you're shelling out at the pump and the grocery store, but, unless policymakers begin to address all three of these trends as one major crisis, it could get …