EDIT: I see my post is being downvoted. I know that it may come across as insensitive to immediately leap to the gun control debate, but frankly I'm more angry than upset by this news. How many times does it have to happen? We have a good 48 hours of emotional outpouring and then everyone forgets it ever happened.
Was the Oklahoma-city bombing a wake-up call for "explosives control"? Was the 2009 Chengdu bus-fire (http://en.wikipedia.org/wiki/2009_Chengdu_bus_fire) a wake-up call for diesel control? Was the Osaka school massacre (http://en.wikipedia.org/wiki/Osaka_school_massacre) a wake-up call for knife-control? Was the 2012 Toronto mall shooting a wake-up call for gun-control in Canada, which already has extremely stringent gun-laws?
It's all too easy to blame the gun in these situations, but guns are just tools, as are knives, and diesel fuel, and even explosives.
It's not the gun. It never was the gun. It's the person.
Then we just have an order of magnitude more of that kind of person than Western Europe. If it's not the guns, then Americans are just worse people, statistically speaking, than our more civilized neighbors around the world.
I live in a country(Lebanon) that went through a 15-year civil war that ended in 1990. Guns are a fact of life here, they are very easy to get and lots of people have them. And yet nobody has ever gone into a school and shot children and parents that I know of.
We've had bombings, assassinations, terrorism, and even a war now and then. If it's violent, we've had it. But not this. Are Lebanese people better people? Hell no. But our societies tend to be more closely knit and more traditional. That has many many drawbacks but it also means that people very rarely get to such extremes in terms of mental well-being(to the point where they could do something like this) without being noticed.
I'm not saying traditional societies are the answer, don't get me wrong. I'm just saying, it's not just a choice between "bad people" or "too many guns". Reality is much more nuanced than that.