I have been shooting and hunting for about 30 years now. I own several guns. I would find it extraordinarily difficult to point any of them at another person and fire. Even in an extreme self-defense situation, I think it would be a very difficult thing to do. I suspect the vast majority of people feel similar (ie it would not be easy to do (if they could do it at all)).
There have always been a lot of guns in this country and they have always been pretty easy to get. If we distributed assault rifles and cases of ammo door-to-door for free, the overwhelming majority of people still would not go on a killing spree. It takes a certain individual/mindset to do it. So while we can (and should) take all facets into consideration, we need to focus more on why people do these things than what they use, IMO. I understand why the attention immediately goes to the guns (and it is important to talk about them and ask if we can make changes for the better (I believe we can)) but we always seem to spend an inappropriate amount of time/effort arguing about guns and not nearly enough on what makes individuals not only want to kill other people but actually go through with it. What has happened/is happening to make people in this country place less value on human life? What is really going on that more individuals seem to be arriving at the conclusion taking out multiple other people (and then themselves) is the way to go?
If we could melt-down every gun today, (tomorrow) individuals would still want to kill others and find a way to do so. We need to work on why that is because we certainly cant eliminate everything someone would use to kill another person.