This comment is very important, because it so perfectly highlights an aspect of the gun control discussion that is so often neglected. Many people believe that gun owners are always 100% responsible and that a mistake like this couldn't ever happen, and are completely shocked and confused when it does. Many other people recognize that humans making mistakes like this (maybe they're sick or tired or something important distracted them in that moment) is something that happens and will always happen.

The former are worried about the world they wished we live in, and the latter are worried about the reality that we actually do live in.