The main point is that kids and freaks should not get guns in their hands. How can you avoid that? If guns are not easy to get. If your mom has in her room, then it's unfortunately extremely easy. Kids will not be rushing to the black market for guns with their pocket money. That's the very reason why in the USA there is such extreme school shooting statistics.
Switzerland is a famous example for Americans trying to defend their little toys. In Switzerland you cannot go public with your guns (except if you have permit, which is very hard to get, only is your profession (security) allows it). The number of weapons is half as much per capita as in the US, but most importantly it's because most men are part of the army. That is a huge difference. This is like comparing the US to Israel.