I think it is reasonable to assume that in general, the more restrictions you put on something, the more people will be deterred. But it is also a tough question: At what point will someone like the Columbine killers or Aurora suspect be deterred. I believe that these shooters in general are very motivated. And in Columbine and Aurora, very smart. Again, it is a tough question as to how far we are willing to go to limit guns from the wide majority of the population in the hopes of stopping some of these shooters. I am not advocating one way or the other, but saying that I think it would take a lot of gun control/restrictions to stop them.
I appreciate all the gun control questions. On that note, there was a fascinating story in the New York Times that I blogged about regarding China, where guns are very hard to obtain. Yet there were schoolyard attacks with knives and other weapons. Again, these shooters will generally find a way. Catching warning signs may be a better help.