With economic hard times upon us, we will be seeing more violence like the horrors in Binghamton New York, and as a result more calls for gun bans. In light of that, I can only link to my post on the Virginia Tech murders from two years ago. I would just have to say more or less the same things over again.*
One small point: As you can see from this map (click to enlarge) New York does not have a shall-issue concealed carry law. What they have is what is known as a may-issue law. What that often means is that, technically, you can get a permit to carry a weapon, but you have to convince the police that you have a "good reason" to have a gun. (A lot of police seem to think that if there is a reason you might actually use a gun then that is a good reason to not let you carry one.)
If New York had, like most of the US, had a shall-issue law, that would have increased the likelihood that there would have been a law-abiding citizen near the atrocity who could have brought the killer down before he shot his last victim and blew his own brains out. As it was, his victims had to wait for the police to respond to a 911 call. The police did a good job of getting there fast (2 minutes, according to the police department) but even that was not fast enough to prevent any murders.**
... unfortunately, I can't make the same point about the multiple murder in Pittsburgh, a story that broke after I started to write this post, in which three police were on a domestic battery call were ambushed by the batterer. There just are no magic bullets for these things (no play on words intended).
* One thing I might change: in the original article, I suggested that the rules should allow any law-abiding person at a university or college to be armed. For reasons of safety, I would now probably support some sort of age-requirement for concealed carry, which could limit it to people 21 and older. Also, it might be good for schools to limit it to teachers and other school staff.
** Later: Looks like I spoke too fast in giving the police even this faint praise. According to this news story: "Police heard no gunfire after they arrived but waited for about an hour before entering the building to make sure it was safe for officers. They then spent two hours searching the building."