But your comments lay the blame on guns- you want to punish the good owners for what the bad owners have done and will do and while you may know a fair number of Americans, don't assume that all people are the same here, or anywhere else.
The two school shootings in Turkey- if these were 'copycat' shootings, I think it's time the media change their ways of reporting these events. People want attention.
I doubt the creators of the Constitution could have predicted what people have become. Sure, bad people existed at that time but nobody should say that people haven't changed into something terrible. Not all, obviously, but the worst? What should be done with them?
How would you force bad people to comply with laws and rules that are more strict? You can't and they won't. THAT'S the problem- they do what they want, don't want anyone telling them what they can/can't do and will kill at the first insult, one bad look or just because they panic, over-react and can't control their anger. But even a hardened killer can get what they want by being nice or manipulative in a non-threatening manner.
I don't want guns to be in the hands of anyone who should never have them but there's the problem- how can they be made to give up their guns? Yes, too many guns are in their hands, but they weren't sold by gun stores and private sellers won't always do it in a legal way (all transfers go through an FFL). Too many guns are stolen, left in a place where they can be found and taken, given/sold to people who'll use them in crimes and since parts can be sold anonymously, guns can be assembled. Simple guns can be built, too- do you know what a 'zip gun' is? Not fine firearms, but they work.
Then, without even considering those who use guns for violent acts, there's the black market that moves guns all the way from local transactions to international- every single person involved has committed a felony- how can they be tracked, arrested/prosecuted and prevented from getting guns again if those people can't be changed?