Honestly, neither side is right. Firearms and weapon related crimes, as well as violent related crimes on the whole, have been on the downturn since, I believe, at least 2005. At the same time, firearm related deaths, crimes, and homicides have more coincidence with handguns than they do with long rifles and shotguns for firearm related deaths.
Mass murders are on the decline, but targeted murders still remain prevalent. Most targeted murderers want to harm their victim, the people directly involved with their feud, and people they perceive as involved. Source: M.S in Forensic Psychology and Counseling with a focus on Aggressive-Prone Individuals. This violent and aggressive prone individual had records of filing HR complaints on other coworkers (as well as the reporter and cameraman) who had filed HR complaints against him. He was described as easy to anger and offend by most of the other staff at WTBJ.
This is not only a gun related issue, but, yet again (BIG FUCKING SURPRISE), a mental health issue. Handguns are not necessary AT ALL. Long Rifles and Shotguns can be used to hunt for sport, to keep populations of animals down (namely deer in this area), and to hunt for food. Guns are not tools for anything else except to kills, intimate, and threaten. If you are hammering something in with the butt of a gun, you don't deserve that gun. It can misfire and kill you or a buddy, or mess with the internal parts to where it will no longer fire.
The unstable individual who killed the innocent reporter and cameraman today would not have been able to do so without a handgun. Even a long rifle or shotgun at such close range would not have been able to get his message across due to how close they were (if you wish to know why I and many others believe he had a message, I'd be happy to answer).
Long Rifles and Shotguns can be useful tools to feed people as well as control populations of certain animals WHEN REGULATED. There is literally 0 need for anyone ever to own a handgun.
"But what about the violent criminals what use them?" I present to you the False Positive Paradox. Imagine you had a population of 1,000 of gun owners, and only 2% of those are mentally unstable/dangerous/what-have-you. 1,000 x (2/100) = 20 people receiving a true positive. 1,000 ((100-2)\100)) x 0.05 = 49 people receiving a false positive.
As evident above, over 5% (and 5% of a population is still a relatively small number) of a population of 1,000 would not use these handguns for violent or homicidal means against another human being. Granted, the above is hypothetical, but still applicable on the percentages, it is by far and above the mentally unstable individuals who utilize firearms to do harm to other human beings.
Criminals will still use illegal methods to do what they do, but regular citizens, without access to those methods, will not do so as often.