In all the rhetoric offering solutions after shooting tragedies, there is a missing ingredient as big as an elephant.
We hear ban guns, hire guards, give mental tests, lock up hazardous people. All that may be OK, but the basic problem is the exclusion of God from our society.
When men emphatically do that, He gives individuals and then societies up to their own choices. Read Romans 1 and II Chronicles 36 in the Bible. How much did we hear about our offenses against God from the media in the current grief and turmoil? Essentially nothing. It seems to be banned.
Nations fall when morality decays. Ban the Ten Commandments and soon we will try to ban weapons to no avail.