I have the greatest admiration for Margaret as representative of an intelligent and strong woman in an age when women were mostly relegated to domestic concerns. She can read people and discern their their strengths and weaknesses, and respond accordingly. Of course, unlike her husband, she doesn't have to murder people to get what she wants. It should also be noted that had she not exercised a certain presence of mind and purloined Nucky's money and papers before the federal authorities could, he would be in a world of hurt.