Awful. As a father, it makes me sick to my stomach.
Two thoughts (the first being more important, IMO):
1) We really need to put a lot more emphasis (and a lot less stigma) on mental health care in this country. Seeing a therapist should be as normal as seeing your primary care physician. I have been seeing one regularly for the past year or so, and it has been very helpful, although I still feel some shame for doing so. (Even though I understand there is no reason for that) Most of these horrific incidents could have been averted had these people sought/been provided help.
2) I'm not an anti-gun crusader, but we do really have an issue with guns in this country. There are 300 million guns in private hands in the US. Far and away more per capita than any where else in the world:
Guns per 100 people (Top ten countries):
United States 88.8
Saudi Arabia 35
Every time an incident like this come up, I see an argument that, "It could have been prevented had some one else had a gun to stop them." I'm sorry, but the answer can not be that we need _more_ guns. We need fewer guns, and fewer assault weapons out there, and stricter checks to getting them (no gun show loopholes, etc). It isn't going to stop all of these things from happening, but it is going to prevent some of them. We should be working towards creating a more responsible gun culture instead of creating a larger and more heavily armed gun culture.
My heart goes out to all the parents in Connecticut today. I don't have the words.