Why are people buying the line that this was driven primarily mental illness

[HooptieWagon]

44. Because it is mental instability that makes a person shoot another.

Because of the moral and legal ramifications, the vast majority of people (including gun owners) accept that it is wrong to shoot another person, self-defense excepted.
Therefore, it is logical to assume that a person who murders a number of people probably has a serious mental problem. 99.99....% of gun owners never shoot a person. Even fewer shoot multiple people.
Facts which the anti-gun crowd always ignore:
There are just over 30,000 gun deaths per year, which is a tiny fraction of the amount of guns and owners. The number of gun deaths has been on a steady decline, despite the number of guns and owners increasing, and the expiration of the AWB. Of the 30,000, over half are suicides (which is a mental health issue itself). Of the remainder, the majority are from handguns. Deaths from assault rifles and shotguns are barely a blip on the radar. Of the homicide deaths, most are committed by felons committing another crime. These aren't legal gun owners who would comply with a gun ban. so they will continue to obtain guns illegally and commit further crimes until they're locked
up. Most of their victims also have felony records. Most homicide victims know their killers. So if you aren't a felon, and don't hang out with felons, you have a low-probability of being a shooting victim. Mass shootings, while horrible, and headline-generating, statistically are a tiny percentage of gun-related homicides. The shooters usually have no felony record, so obtaining weapons is incredibly easy for them. This is all from FBI database, which I looked up online after Aurora shooting. Invite you all to do the same.

It seems pretty obvious to me that a mass killer is mentally ill. So the gun death problem isn't with the 99.99+% of gun owners who never shoot a person. It is with the career criminals (problem solved by locking them up), and with making access to guns so easy that mentally disturbed individuals (who haven't yet committed a crime) can readily obtain them. However, the problem will never be solved. The anti-gun crowd blames the 99.99...% of gun owners who will never shoot a person, and want all guns banned or similar nonsense. In the meantime, the gun lobby wants to make gun-ownership easier, because it increases sales. Most gun owners would support greater controls, keeping guns away from crazies, if they were assured popular models of guns wouldn't be banned. Less than 10% belong to NRA...I think more may belong to one of the non-politically affiliated organizations. The NRA and gun lobby is funded by manufacturers and retailers, only a tiny amount of funding is from individual members. Anyway, no solution will be reached when it's driven by misinformation and an emotionally-driven knee-jerk reaction.