Five years ago a gunman killed 32 people on the Virginia Tech campus in America's worst mass shooting. Two years ago a gunman critically wounded former Congresswoman Gabrielle Giffords and killed six people. Two months ago teenager Travon Martin was shot and killed by a neighborhood watch volunteer in Florida. Each time a tragedy involving firearms becomes national news, advocacy groups and politicians call for stricter gun control. But little action has resulted. Pro-gun groups argue violent crime in the U.S. is a major reason to expand gun rights, so more Americans can protect themselves. Diane and her guests will explore the politics of gun control.