Politics is the art of the possible, as the saying goes, and the possibilities for the 2013 Farm Bill will be shaped by a number of political factors. We are best reminded of that truism by the recent compromise on immigration reform, which was negotiated by a bipartisan group of eight senators, ranging from Senator Chuck Schumer (D-New York) to Senator Marco Rubio (R-Florida). Today we thought we would list what we see as some key political issues that have to be addressed and/or finessed to get a farm bill. Some of them fall outside the economic and commercial issues that face U.S. agriculture.Nutrition: Last year we frequently commented that Senate Ag Committee Chairwoman Debbie Stabenow (D-Michigan) is from a state with a large number...