Many of the proponents of gun control believe that a prohibition or restriction will somehow keep people safer. All of the things that they propose are passive measures. Licensing, registration, micro-stamping, banning certain classes of firearms and ammunition - all of these are passive measures.

Without complimentary active measures these plans have no hope of success. Making a rule that cannot be enforced only effects the people that choose to follow the rule.

A metal detector is a passive measure and with out a couple of armed guards it is useless. Someone has to force compliance, otherwise the metal detector beeps but with no one to stop the subject it is simply an expensive noise.

Everywhere you want to create a 'gun-free' zone, you need to create a security perimeter. A wall with cameras is another passive measure, and without a guard force to patrol or respond to someone penetrating the perimeter the physical barriers become useless.

The armed guard is a weakness in the system. You will need a large number of armed guards into make the system work and everything revolves around the armed guard being trustworthy. If we increase the number of armed guards, we build in some protection for a single guard being corrupted, crazy, or overpowered.

By hardening the target we have made it very difficult penetrate, but vulnerabilities still exist. As people enter or leave the facility en mass they are vulnerable and staging the attack for the arrival or departure time defeats all of the internal security in our facility.

The costs of recruiting, training, and funding such a guard force are significant. Scaling such a system up to protect every school, shopping mall, and church would be astronomical.

Instead of building a fortress around each school, we could simply build a fortress around the nation. Assuming we could confiscate most of the 270 million small arms that are privately owned in this country we then face the problem of preventing any additional weapons from entering the country. This would require a major overhaul of our global trade practices and immigration policies. I am not sure there is a way to do this, since drug smuggling and illegal immigration are so prevalent. We can't keep drugs out of our prisons, I don't believe we can secure thousands of miles of coastline and overland borders.

Maybe focusing on trying to defeat a tactic or particular tool is the wrong way to go about this. Perhaps more stringent mental (and moral) health screening is the way to mitigate the root causes of both murderous rampages and violent crime. If these individuals were flagged for treatment or reeducation we could institutionalize them before they were able to act.

Another alternative is to accept that the guarantee of perfect security is a lie. Accept that bad things are going to happen, despite our best precautions and focus on mitigating the event at the time it occurs. The people have a selfish self interest in their safety and survival. Allowing the people the means of solving the tactical problem will lead to greater safety.

Mass shootings are rare, that is why they capture so much media attention. Even simple homicides are pretty uncommon statistically, despite the prevalence of firearms in private hands. The fact is that the vast majority of the population are not violent criminals or lunatics. If this were not true the violent crime rates would not be a topic of discussion, but rather an omnipresent concern in our day to day lives.