Wisconsin Gov. Scott Walker is in trouble in his re-election campaign, so he's going back to a strategy that's served him well: divide and conquer. Walker's new plan involves targeting some of Wisconsin's most vulnerable by requiring drug tests for unemployment insurance and food stamp applicants, while using the fact that that's illegal to pick a fight with the federal government: Few details were included on the new proposals, but advocates for the needy said the drug testing proposal for jobless and food stamp benefits would violate federal law — a complication that killed a similar proposal promoted by Republican lawmakers in 2011.