I think that's simply the effect these things have on about half the population
Imho, the gun issue is lost. For far too many Americans, it *doesn't matter* what outrage is committed with firearms--they won't accept anything they feel is an intrusion on their constitutional right to arm themselves to the teeth.
When a classroom full of children is murdered at gunpoint, and the collective reaction of the country is a shrug...America is lost, and that's how it will remain.