I find the gun debate really interesting, because on the one hand as someone who has been shooting for fun I can absolutely understand why people get defensive about it. If you’ve only ever used your firearm to target shoot, it must feel like a huge imposition to have to change your life to cater to the criminals who kill children.
That being said, there is extremely strong evidence from around the world that gun legislation — things like national registries for guns and ammunition, strict control on semi-automatics, and strong licensing that requires yearly renewal — reduces the number of gun deaths, gun homicides, and mass shootings specifically. There really is no question. Mass shootings are almost exclusively a US problem in all of the developed world. There may be one or two a year elsewhere, but in the US it’s one or two a month.
Securing schools is not only incredibly expensive (think about how many schools there are), it is likely ineffective, and there is a proven solution that has worked everywhere else in the world. Would it have to be modified for the US? Of course. Is the basic structure there for anyone to see? Absolutely.