I doubt anyone can "guarantee" how things will be developed in few decades. Noone knows for sure how the policy will transform societal relationships.

Presence or absence of weapons doesn't affect if someone will use it or not. Getting or making a weapon is relatively easy task even in Japan.

Growing a cohesive society where people use other means to cooperate instead of assaulting everyone who disagrees with their opinion is most important

> Presence or absence of weapons doesn't affect if someone will use it or not.

Yeah No. When weapons are absent, the probability of using a weapon is exactly 0.

When weapons are cheaply and easily available, the probability is definitely not 0.

Those who wish to create mayhem, can and will, get weapons one way or another. Happens all over the world. No amount of laws or severity of punishments can change that.

But, gun restrictions prevent impulsive actions, and actions or situations exacerbated by the false security that having a gun gives, or plain right idiots who don't know how to safely handle guns.