A total of 4,553 motorcyclists died in traffic accidents last year in the United States, but more than 700 of them would have lived if they had been wearing helmets, Mary E. Peters, the new U.S. transportation secretary, said Thursday in Milwaukee. Peters, during a visit to the Harley-Davidson plant in Milwaukee, talked about the "alarming rise" in fatalities and injuries involving motorcyclists since 1997. Peters, an ardent motorcyclist, said she will "never, ever ride without a helmet." She said a helmet last year saved her from more serious injuries in an accident in which she hit her husband's motorcycle...