Banning guns or deploying armed forces won't solve the problem. I don't think high-school students or middle-aged men commit violence like this spontaneously.
Somebody who kills random people or himself or both can do that when he has no hope left from anybody, society, system, family, friends, etc.
Leave aside politicians, corruption and violent history. I feel it is about general people.
There is no "problem" - unless We count the fact that the psychopaths in control on Our planet, who create these psyops and sell them to Us as "reality," are a problem. Which I consider Them to be. I would solve for psychopaths in control, and if You would too, I invite You to watch the playlist I have on YouTube. Do watch on YT, as only the first vid plays here. (The whole list is less than 1 hour's worth of vids):
What's new about it? Genghis Khan, Sultans of Delhi, Alexander, Colonialists, Many Knights, Many Samurais n I don't know how many warlords have killed zillions of people & shaped the history of the world.
A person who kills one person is a murderer.
A person who take assignments for killing is a hitman, soldier or sepoy.
A person who kills random people is a psychopath.
A person who kills too many people and cause a lot of destruction is a terrorist.
Which army in the world does't kill millions of people?
All the armies are backed by their community morally, financially, emotionally and every possible way.
A person who kills or orders to kill millions of people is a warlord, king or emperor.
The world is not good, neither bad, it's not accurate to call it any of the two.
Psychopaths who kill random people on the street don't come from the Mars. Cancer has its roots within the body(Society). When the DNA inside of the nucleus of a normal, healthy cell gets altered in a bad way, it starts killing cells around it. Though, previously, it was exchanging resources and wastes with all of them.
The negative thought processes are like dysfunctional DNA. Why exactly somebody thinks in a negative fashion, it's too difficult to figure out.
According to me, there's no solution to this unless the whole society evolves into a saint-like society. I don't think it's happening any time soon.
Who said anything was new...? [smile] Indeed, it's the oldest game on Our planet. If You examine what I propose, You will see that the structure, the foundation, allows for no "authority" - without the accounting for Human energy added into a system that accounts for Human energy added (money), the psychopaths have nothing for widespread influence, no longer able to pay strong arms and armies. No longer able to bribe, set up blackmail scenarios, threaten, ruin, or kill (through Their strong arms). They have to do Their dirty work PERSONALLY.
If We abandon the systems (which belong to the psychopaths), and consent to what I suggest We do, a truly free and healthy society will emerge. No "saint-like" behavior required.