That's a really good read. One little talked about event during this shooting is early on a hotel security guard (presumably unarmed) was shot in the hall right at the beginning of the shooting. That article also mentions the landmark supreme court case where its ruled that law enforcement doesn't have a duty to protect citizens.
Private security in this country is a joke. It's a cash grab to provide the bare minimum security insurance requires with the most unqualified people. They are more concerned with busting pot smokers at concerts and confiscating grandmas scissors at the airport then protecting people.
When there were important people involved it was a different story. Riding tbe el or Saturday on the running trail I'd often see the mayor of Chicago totally unescorted. But I'm sure if you attacked him youd be dead before you hit the floor. Or at the G8 protests or when the president rolled through town there were no secure checkpoints, but if you looked up you could see the snipers. Same with the Cubs and Blackhawks championship parties. Unsecure areas with a security presence looming to keep order.
I hate this fake security theater. If we are going to give up our freedoms for for security at least let's get some benefit out of it. If a venue traps people due to an unforseen fire or collapses due to an unforseen earthquake they are liable. Mass shootings have been a threat for 50 years, bombings at events were common around the turn of last century.
Start making private event and company owners liable and you'll see a change. Unfortunately the Aurora theater case didn't go that way.