Since the deadly mass shooting in Tucson, three high school students have been shot near Los Angeles and a gunman killed two police officers in Miami. But there's been little support for new gun controls, in Washington or anyplace else. President Obama and White House aides have avoided the issue. In the past, mass murder and the killings, and attempted killings, of public figures have led to restrictions on guns, but times have changed. Recently, even those incidents that have worked their way into the language —Columbine, the DC sniper, Virginia Tech — have not. Have Democrats lost their nerve? Has the NRA won the battle? We hear from pollsters, reporters, the Brady Center to Prevent Gun Violence and the world's biggest gun trade show, going on now in Las Vegas.