Rahm Emanuel, current mayor of Chicago, is not a gentle soul, writes John Stossel. But he's smarter than his big-spending predecessor, Richard M. Daley, and the union pawn, Jesus "Chuy" Garcia, who becomes the new mayor if he beats Emanuel in a run-off election April 7. Emanuel was the tough Obama chief of staff who reportedly stabbed a table with a steak knife as he listed political enemies. He relishes conflict and famously said that in politics, "You never let a serious crisis go to waste." That comment scared libertarians and conservatives, who know that government usually uses crises as excuses to increase its power. But here's the surprise, writes Stossel: Emanuel has been in crisis mode for four years now, and sometimes he made the right decisions as a result.