While I am a RKBA supporter of the first order, there's little ANYONE can do about someone 100+ yards out who knows how to shoot a rifle. By the time I hear the shot (if I know exactly where it came from,) and get within good range w/a semiauto handgun, the perp could be in Texas.
This series of incidents does not make a good argument for CC permitting--nor, obviously, for confiscating all the registered firearms in the USA.
This series of events DOES make a good case for being prepared to meet your Maker.
What you say is true but people who have been around guns a little more would have an edge if they were the witnesses.
If there would have been at least one person familiar with firearms nearby, they could have figured out the direction and how far the killer was. This doesn't mean that someone would have to go charging toward the killer like he was storming a beach. It only means that someone would be able to tell if the person really was in those trucks or hiding near one and using it as a decoy.
This hasn't been a lack of police work. It's been a lack of witnesses or let's face it, any credible witnesses, at the scenes.