President Obama took the high road at last night's memorial service in Tucson, asking Americans not to use "tragedy to turn on one another." At a time, he said, when political discourse is "sharply polarized," we should talk "in a way that heals, not a way that wounds." Republicans are now on a closed-door retreat, talking about the business of trashing healthcare reform under heavy pressure from Tea Party supporters. Did Obama meet the challenge a president faces in troubled times? Will politicians and pundits tone down the rhetoric?