When legendary David put down giant Goliath with a sling and a rock, his victory was largely the result of using some available but unconventional appropriate technology to solve a critical problem.
It's worthy of note that the locals in the neighborhood are still creatively murdering each other using all the tools available, including rocks, a few thousand years hence. One might venture to say: "Religion and Murder are the mare's milk of the Middle East. " Also: "Rocks are dangerous weapons."
I suggest that people seeking a sense of proportion might review the history of this and related topics with "rock" substituted for "gun".
Technology begets technology. Modern airplanes are full of machines, devices, tools, equipment, and facilities intended to make the transportation process operate better and more safely. Many of these are either inherently dangerous or amenable to serious misuse if the operator is careless, stupid, or malicious. All of these are, in one sense or another, under control of the flight crew. We have to hope that they will be trained to use them skillfully and effectively as may be necessary. Bankers and insurers usually insist on it. Psychiatrists and other docs and lots of managers watch over it And the evidence to date shows that the system works pretty well.
Guns are just another embodiment of technology - a means for projecting force across a distance. A fire axe or a common screwdriver can cause many of the same negative outcomes that are seen as the downside of airborne guns. Just like rocks, it's all in how they are used.
Skillfully, one hopes.