 Wisconsin Senator Ron Johnson's assessment of security at Saturday's rally where a gunman shot from a nearby rooftop. He tells CBS Mornings. This is security failure. I think we all assume that, you know, any kind of high rooftop is totally covered, totally secured. I mean, particularly after JFK's assassination. The investigation into the gunman is picking up steam. Correspondent Scott McFarlane is in his hometown of Bethel Park, Pennsylvania.