"Now and then a moment occurs that clarifies the nature of American politics like a flash of lightning over a prairie landscape. Such a moment occurred on Sept. 9 during President Obama’s televised address to a joint session of Congress about healthcare. As the president explained that illegal immigrants would not be eligible for benefits under the plan he supported, Joe Wilson, a conservative Republican member of Congress from South Carolina, shocked the chamber and the television audience by shouting, 'You lie!'"