Doctors say smoking is a major cause of health problems in the US, but cigarettes are still legal. Now four of the five big tobacco companies have sued the Food and Drug Administration for relief from requirements that they put graphic warnings on their own products. There's a picture of a corpse with its chest sewed up and a warning that "Smoking Can Kill You." Another image shows a pair of lungs that are yellow and black with disease. Such warnings will be rotated on cigarette packs and take up more space than their brand identifications. Duff Wilson reports for the New York Times.