In the 1980's, gun violence was declared a public health issue, but Congress blocked research into prevention by the Centers for Disease Control and the National Institutes of Health. In 2012, after the Sandy Hook massacre, President Obama proposed to resume that effort, and some Republicans agreed. What's happened since? Since the first of this year 5,823 people have been injured by guns and 3,479 have been killed. That's according to the Gun Violence Archive. Is there an "epidemic?" Could efforts to stop it stop short of gun control?