The solution is security, not bans.
There is little difference between crazed madmen, zealots, or terrorists who are bent on destruction.
What would we expect if 20 children and 6 adults had died in Sandy Hook at the hands of a terrorist that was screaming invocations to his deity? What if the victims had been blown up by an anti-government zealot with a truckload of fertilizer and diesel fuel?
Because of the truck bombing of the Murrah building in Oklahoma City; most Federal buildings are protected by elaborate measures outside, and armed guards within. Look closely at the new federal courthouse in Cedar Rapids.
Immediately after 9/11, we posted 5000 soldiers at vulnerable sites throughout the country, 8200 were deployed in airports until enhanced TSA security measures could be implemented.
It’s nearly impossible for the criminally intentioned to carry any imaginable weapon near an airliner. If one should get aboard, there are armed pilots and/or air marshals on many flights. If terrorists get into a federal building, there is armed security within.
Banning specific weapons or accessories will do no good. Because we really do know it is not the implement, but the perpetrator, who wreaks the devastation; we have not banned box cutters, airplanes, fertilizer, rental trucks, or diesel fuel.
Guard our children with returning troops. Many would likely volunteer for such duty. Retrofit schools with measures equal to federal buildings. Secure the interiors with armed resource officers and voluntarily trained, armed staff.
Our future generations deserve no less. Protect our posterity.